abundant in the vicinity. The triangle formed by the lake, the Geysers, and St. Helena-each about twenty-five miles from the other two-abounds with volcanic scoria, trap, lava, obsidian, tufa, warm springs, and other remains of eruptions, and signs of subterranean heat at no great distance from the surface.

The sulphur-bed of Clear Lake is about eight miles from the southern end, on the eastern shore, only a few hundred yards from the water. There is a bank resembling ashes, in which there are numerous alkaline and sulphur springs, and, also, vent holes from which sulphurous fumes escape. These holes are surrounded by beautiful crystals of pure sulphur deposited from the fumes rising from below. The earth, containing about fifty per cent. of sulphur, is placed in an iron retort, which is heated to a high temperature, so that the sulphur is driven off in fumes into a receiver, where it settles in a liquid form, and runs out into pine boxes, 2 ft. long and 1 ft. square. It is as

pure as the Sicilian brimstone; but the latter comes in sticks, which are more convenient for handling, when small pieces are wanted.

The lump sulphur is used chiefly for making powder and sulphuric acid, which last is employed in making blue-stone, giant powder, nitric acid, and muriatic acid, and in refining gold and silver. The consumption of sulphuric, nitric, and muriatic acid on the coast amounts to 2,000,000 lb., and the entire demand is supplied by home manufacture.

Lately the production of flowers of sulphur has been commenced at Clear lake. The fumes passing off from the retort, instead of being carried into a small hot receiver as for brimstone, are led into a large cool chamber, in which they condense into a flaky, snowlike condition. This form of sulphur will be needed in large quantities next spring and summer, as a cure for the mildew which attacks the vines, and did great damage in many of the vineyards last year.-Alta, California.

ANIMALS AS FELLOW-BOARDERS.

BY P. J. VAN BENEDEN.

IN THREE PARTS.-PART I.

¿Male.

PAPER by M. P. J. van Beneden was recently read before the Belgian Academy, on what he termed the commensalisme, commensiolity, or literally, commontableisme of animals, describing the habits of creatures who may be said to board together, but whose association is distinct from that of victim and parasite.

Every fish, he says, is a living and moving territory, on which a fauna is developed possessing special interest. When a small animal claims to profit by the fins of one larger than itself, accompanies it in its chase, and picks up spoils which the larger one disdains or abandons, we see none of the motives which characterize parasitism. Even when one resides upon the other, it frequently does not deserve the term which is applied to it. It is not rare to find loyal companions by the side of generous hosts, rendering service in return for the hospitality they receive. The parasite makes it his business to live at the expense of another; the associate is simply a table companion. When a whale is covered with barnacles, who can say that these Cirripeds are parasites ? They merely ask of their colossal companion a lodging-place, and they are not more dependent upon him than coach travellers or railway passengers: they feed themselves on their journey. Leeches behave quite differently: temporarily attached to the skin of their host, they suck his blood, and drop off after their meal, that they may conveniently digest it. They are not deemed parasites, because they leave their host during the intervals between their meals; but this is an erroneous opinion;

Presented by G. Wilks, Esq., C.M.Z.S. Ditto.....

Ditto..

Presented by Dr. R. S. Peart... Presented by Mr. E. Chimpson

Purchased..

Ditto....

Deposited by E. O. Blake, Esq.. Ditto..

Born in the Menagerie

Female.

Sheep-sheds Carnivora-dens Falcons' Aviary Winter Aviary Vultures' Aviary Parrot-house Reptile-house Parrot-house

Ditto

Eastern Aviary
Ditto
Goat-sheds

for they are true parasites, as the barnacles are true companions.

There are many animals living in common whose relation to each other is not well appreciated, and it will not be uninteresting to glance at these, and endeavour to form a notion of the ties that unite them. We do not mean to speak of those associations which are known as flocks and troops, composed of individuals of the same species united for defence or attack; or of different sexes, neuters, workers, soldiers, &c., which belong to the same family. Our purpose is with associations of different species whose members bring together their energy, their intelligence-I might say, their capital, and become fellowboarders, living on terms of perfect equality; although it is not uncommon to see the strong use up the weak, or the evildisposed slip in amongst peaceful communities. The sea-bed has its bravoes and fiers-a-bras.

Amongst fellow-boarders we see some that preserve all their independence, and who, at the least cause of discontent, break the connection, and seek their fortunes elsewhere. They are recognized by their apparatus for fishing and travelling, which they never put aside. Others install themselves upon their neighbours, throw away all their travelling gear, make themselves comfortable by a change of toilet, and renounce for ever their independent life. Their lot is fixed to the creature that carries them. They are permanent fellow-boarders.

Let us consider, first, free fellow-boarders. We find free fellow-boarders in different classes of the animal kingdom. Sometimes they sit on the back of a neighbour; sometimes they go in at his mouth, and follow the route of his food; and sometimes they take refuge under his cloak. An interesting instance belonging to this first category is afforded by the graceful fish, the Donzella, which makes its abode in the body

April 27, 1870.]

of a Holothuria.

The Donzella is elongated like an eel, and so compressed that it has been compared to a sword. It is found in different seas with precisely the same habits. The fish lodges in the digestive cavity of its companion, and, without regard for the hospitality it receives, takes its share of everything that enters. It makes use of a generous acquaintance, who can collect food better than itself. The Holothuriæ, or sea-cucumbers, are excellent fishers, and we often find in them, side by side with the Donzella, who are probably gluttons, prawns and pea-crabs, who come for their part of the spoil. My friend C. Semper has seen sea-cucumbers in the Philippines who were not bad imitations of an hotel furnished with a table d'hôte.

In the Indian seas a fish is found known as Oxibeles lombricoides, modestly lodged under a star-fish (Asterias discoides), and taking advantage of its fishing powers. In Brazil, a Siluroid, of the genus Platystoma, a clever fisherman, thanks to his numerous lines, lodges very small fish, which were for a long time supposed to be its young. It was thought the female kept her young in her mouth, as the marsupials keep their infants in a pouch; but it is now known that they are adults and completely developed, but instead of living by their own labours, they prefer to lodge in the mouth of a good-natured neighbour, and take tithe of the food that comes in. little fish has received the name of Stegophilus insidius. We see that in the animal kingdom it is not always the big which make use of the little.

This

Dr. Bleeker, an able naturalist who has rendered good service to science, makes us acquainted with an association of a still more remarkable character-that of a Crustacean who makes use of a fish,—the black Stromatée of the Indian seas lodges in in its mouth a Cymothoa, who, if not well adapted for catching his prey in a free state, is perfectly organized for swallowing what comes to him in this position. In the China seas Dr. Collingwood found an anemone not less than two feet in diameter, in whose interior lively little fish resided, the name of which he did not know; and, without quitting our shores, we may observe an elegant jelly-fish (Chrysaora isocela ?) sheltering many young scad (Carane trachurus), which surprise us by swimming out from the body of their host.

It is, however, amongst the Crustaceans that we shall find the most remarkable examples of free fellow-boarders. The Crustaceans comprise lobsters, crabs, cray-fish, and legions of small animals who act as the sanitary police of the shores, and purify their waters of organic matters that would otherwise corrupt them. They are not like the insects, variegated and glittering in colour; but their forms are robust and diverse, and they often please by some special attraction. Among these Crustacean free-boarders one of the most interesting, though one of the least, is that tiny crab, the pea-crab, which lives in mussel-shells, and has been wrongfully accused of injuring the quality of their hosts as food. They have been very numerous this year, but cases of mussel-poisoning have not been more common than usual, and when such effects occur, it is the mussels themselves that are to blame. They produce a bad effect on some persons by idiosyncracy-we know the word though we do not know the thing.2 For what reason do these small crabs, the Picnotheras of naturalists, which are not found elsewhere, inhabit these bivalve mollusks? The ancients, who knew the pea-crab of Pinna, thought that the mollusks having no eyes were glad to avail themselves of the good sight of the crabs. These, like other Crustaceans of the same rank, carry on each side of the carapace, at the end of a movable support, a charming little globe, furnished with hundreds of eyes, which they can direct, as an astronomer turns his telescope, to any part of the firmament. What cannot be doubted is, that the

In a note, M. van Beneden says naturalists have long known these fishes as Fierasfers. They are allied to (voisins) Ophidium, eel-pout or harbolt, and sandeel-fishes which are very dissimilar. It is the sand-eef particularly the Donzella is said to be like.-ED.

2 Particular mussels often produce poisonous effects on persons with whom this species of food usually agrees. This probably arises from a particular state of the mollusk rather than of the person they injure.-ED.

little intruders live on good terms with the mussels, and if the latter supply a convenient and safe lodging, they on their side profit largely by the morsels which fall from the claws of their guests, who are well placed and well provided with prey-catching apparatus. Snugly seated in their living house at the bottom of the sea, they possess a movable lair which the mussel carries about, and they can choose the best moment for attack, and fall upon the enemy unawares.

Pea-crabs are found in all seas, and in a great number of bivalve mollusks; the North Sea even containing a large sort of mussel, Modiola papuana, found in deep and difficultly-accessible spots, which always contains a couple of pea-crabs as large as a hazel-nut. The great Avicula (Avicula margaritifera) which furnishes the oriental pearls, also lodges pea-crabs of a particular species, and it is not impossible that these creatures, and similar fellow-boarders, contribute to the formation of the gems, since these objects, so highly prized for feminine decoration, are only the results of vitiated secretions, most often produced by wounds. We have opened hundreds of these Aviculæ, and have never found them destitute of their crabs, many of which we placed long ago in the Museum of Natural History in Paris.

We also find pea-crabs in the great clams Tridacna gigas, whose shells might serve for a bénitier in the churches, and no doubt they would be discovered in many bivalves not yet considered.

On the coast of Peru there is a little crab which lives under rather different conditions. He chooses not a bivalve mollusk, but a sea-urchin, lodging in its anus, ready to seize any creature who may be attracted by the excreta. There is likewise a small crab, Hopalocarcinus marsupialis, which dwells amongst the depths of the thick branches of a coral found in the Sandwich Islands, and is at last completely inclosed in the dividing

stems.

An association of a different kind, and the nature of which is difficult to appreciate, is that of a little crab, the turtle crab of Brown, found in the open sea on the carapace of sea-turtles, and sometimes on sea-weed (fucus). The sight of this crab is said to have given confidence to Columbus eighteen days before his discovery of the new world.-The Student.

A GEOLOGICAL DREAM ON SKIDDAW.

BY J. CLIFTON WARD, F.G.S.

IN THREE PARTS.-PART III.

OR a vast period did this ocean prevail, and then for as vast a period unsettled movements, during which nearly the whole of England was brought above water, and much previously-deposited matter swept away, while life itself underwent a slow, though complete, change.1

Finally, the south-east of England alone became sea.2 The climate seemed warm, or sub-tropical, and currents bore into this ocean Gulf fruits and fragments of trees from some not far-distant spice islands.3 Monkeys and other mammals inhabited the land, crocodiles dwelt in the crecks, turtles crept along the sea-shore, serpents lurked in the forests, and sharks innumerable thronged the sea.

Once more, however, a cold period returned, which was succeeded by another warm and genial age, when, at first, a long island, or continental isthmus, separated a northern from a southern gulf, while afterwards nearly all but the southern edge of England was above water, that part being occupied by estuaries with scattered islands. Now flourished forests of oak, elm,

beech, firs, and pines, among which wandered curious and antique mammals, some uniting the characters of the rhinoceros and the horse, some more like the modern tapirs,' and various other forms, while tiger-like carnivores roamed the forests for their prey.

So, I saw in my dream that centuries after centuries rolled on, England became wholly dry land,' old life died out and new appeared, an early form of elephant,10 and the deer tribe, with a three-toed horse," and others, taking the place of the former inhabitants, and forming links between them and those to come. But cold again set in, and drove many of them farther south into warmer climes.

12

A long period elapsed, the eastern parts of Norfolk and Suffolk sank beneath the sea;13 warmth once more returned; the elephant and rhinoceros, tapir and horse, ranged the country; tigers and bears roamed over the land, and hippopotami waded in the rivers.

Long did this condition of things last, during which time, and for the long ages preceding, in which the greater part of

culture is introduced among those who hitherto, had lived solely by the chase.

As time wore on, I seemed to watch the gradual development of man's mental capacities; but long ere his present state was reached, I, long time enchanted by the sight of changes so many and so vast, awoke, and starting, found myself, with evening shadows falling, still on Mount Skiddaw. Thence I hastened, my mind all eager to see if these things were so; and soon I saw rocks formed of ancient mud containing mummies of lowly organisms, 16 beds of ancient lava and ash,17 roots of old volcanoes;18 numerous wide and deep valleys, the result of ages of atmospheric wear and tear; hollows now filled by lakes; and rocks, smoothed, polished, rounded, and scratched, as ice alone can do.20 And, as I thought on these things, Chaucer's wise saying came to my mind

19

"Many men sain that in sweveninges 21 There n'is but fables and lesinges; 22 But menne may some sweven seene Which hardely 23 that false ne bene.

14

But yet again the climate changes, and snow-capped mountains and ice-covered country succeed to genial warmth. Many of the inhabitants of land and ocean retreat southwards; others, such as the elephant and the rhinoceros, become adapted to the cold by assuming woolly coats. Over the frozen plains which these inhabit range large oxen, bisons, and reindeer, while cavebears and hyenas leave their dismal haunts to roam in search of food.

Now, however, a change comes over the country of a nature not seen for many an age. Slowly and quietly the whole land sinks down beneath the ocean, excepting quite the southern part, and the higher points of the present Wales and Cumberland. In these last spots occur groups of islands,15 each a little nursery of icebergs.

As the land once more rose to nearly its former level, the glaciers again for a time filled the valleys, deepened and scooped them out, wore down, smoothed, and scratched the solid rocks over which they flowed, and still further polished the country. The animals which had retreated southwards on the sinking of the land now gradually return, and with them, traversing the plain connecting England with the Continent, comes man, rude in the arts, using flint implements, living on the produce of the chase, and maintaining an active warfare with the beasts of the land.

Smaller and smaller grow the glaciers of Wales and Cumberland, and many a hollow, occupied and formed by them, becomes the nestling-place of some smooth and mountain-reflecting lake. The never-ceasing action of atmosphere and sea, aided by a slight depression of land, next severs England from the neighbouring continent, and man, though savage first, and as untamed as the wild beasts he hants, becomes slowly civilized by contact with more advanced races, who seek out this island home, and who absorb or drive away the weak and savage aborigines; in this way, rude stone implements give way to those of metal; cave dwellings to rudely-built huts; and agri

A NOTICE OF RECENT OBSERVATIONS ON AMOEBÆ AND MONADS BY RICHARD GREEF AND L. CIENKOWSKI.

BY HENRY E. FRIPP, M.D.

IN THREE PARTS.-PART II.

N the question of the casual connection between life and organization introduced by Huxley in his prefatory remarks, I shall, if time admit, say a few words after we have become acquainted with the new species of land Amoeba described by Dr. Greef. Suffice it here to say that, without straining the terms of Huxley's own definition of Amobæ, organizations of a very definite kind may be claimed for animals which possess a nucleus and contractile vesicle, and present an approach to a sexual mode of reproduction, besides multiplication by division of substance.

In his Hunterian Lectures (1868), Huxley specially mentions the nucleus and contractile vesicle of Amoeba, their multiplication by fissure, and by a low form of sexual reproduction. The Amoeboid stage of the Gregarinida, ending in an encysted condition, in which reproduction by pseudonaviculæ, is also maintained by Huxley. The observations of Greef considerably augment our knowledge of structural changes, and of the mode of reproduction of the Amobæ, and tend, as I think, to modify the broad assertion that these animals have no organization in the strict sense of the word.

To Dr. Greef's account I shall now direct your attention. And first, in respect to their habitat and mode of life. Dr. Greef finds these animals very commonly present in sand, and at the root-fibres of mosses, grasses, and other plants which grow in shallow mass upon stones, rocks, walls, houseroofs, trees, &c., that is, upon a firm bottom. They appear, therefore, in exactly the same places as the Arctiscoidæ, wheelanimalcules, anguillulinæ, &c., e. g., in the sand under thin liverworts and lichens, and are found generally in company with these, may therefore be sought for wherever these creatures are found. Dr. Greef, however, has often searched for them in vain where the above-mentioned animals exist in abundance, while at other times a numerous population of Amœbæ is to be seen under every moss examined. The conditions favourable

to their presence Dr. Greef has not been able to determine with accuracy, but considers that a position exposed to the sun, and the greater or less abundance in the earth of small Diatomacea and other Algæ, which naturally constitute their chief aliment, must materially influence their presence. As to their condition of life, these Amoebæ, living generally in company with Arctiscoidæ, must share in common with them the power of withstanding a high degree of dryness for a long time. The nature of their habitat renders it certain that a rapid drying-up of the earth or sand, especially in summer, must often occur, during which the active life of the Amoeba is interrupted that is to say, the creatures become torpid, just as the Arctiscoidæ do, a fact which Dr. Greef has shown in an essay on these latter animals (2nd vol. of Schultze's Archiv). Their power of retaining life is indeed wonderful. The outer tough coriaceous but transparent layer draws together as the surrounding medium becomes drier, and thus protects the inner softer granular parenchyme from drying up. In this perfectly motionless and apparently lifeless state, the creatures are met with in dry sand, from the particles of which they are scarcely to be distinguished. But by moistening the sand in which they may have dried up thus for months, they regain quickly an active existence.

These species will be characterized after we have given Greef's description of his typical Amoeba terricola.

This creature, found in dry earth and sand, looks exactly like a small particle of grit or silex, having a dull glassy surface, and a number of short, stiff, knoblike protuberances on its external surface. The body is of irregular shape, and divided by clefts or fissures; it contains in its interior a number of yellow or brown coloured granules, which are seen in pretty active motion, streaming hither and thither as they are impelled by the movement of the contractile sarcode. The locomotion of this land Amoeba differs strikingly from that of the water species. Its external transparent ectosarc is of a much firmer and tougher consistence than that of the water Amoeba, and the contraction of this ectosarc is much more powerful. The knotty protuberances do not spread with a smooth, flowing motion like the projected masses of the water Amoeba, but remain stiff. The outer surface is wrinkled into folds, meeting and crossing each other when the animal collects its endosarc into a globular mass of comparatively small size (as, for instance, when resisting the pressure of the covering glass), exhibiting great contractile power. After a moment of rest, the animal projects its sarcode in a broad stream towards some point of its periphery, while at the opposite point the sarcode contracts and governs the direction of the forward movement until the animal falls over by change of its centre of gravity, and thus, by a series of rolling movements, it makes its way. The projected arms appear to seek the free spaces between the particles of earth or sand in which the creature is moving, and thus the direction of movement follows the line of least resistance. The movement results from the strong con

1 This movement cannot be called creeping. When, by a change of centre of gravity, the animal rolls over, the firm protuberances do not yield or flatten, but present blunted ends, on which, as on points of leverage, the creature is upheld in its rolling gait backwards or forwards. The movement is often very active, and carried on with energy and grace,

traction of the ectosarc at the point opposite to that of the yielding surface, which allows the endosarc to be pressed forwards. During these movements the whole of the interior can be seen in turn, and peculiarities of structure are thus best observed.

The distinction between the tough ectosarc and semi-fluid inner mass is much more marked in land than in water species of Amœbæ. Greef remarks that the body must be composed of two kinds of plasm greatly varying in consistence and physical appearance; the outward hyaline ectosarc, firm in substance, the inner mass soft and granular.

Wallich and Carter have noticed a similar differentiation even in water species. Wallich distinguishes the outer and inner portions as ecto and endo sarc, but appears not to have found any differentiation of contractile capacity or physical constitution. Carter recognizes a difference of substance and property between the outer and inner sarcode. In the clear ectosarc, which, according to Carter, has a distinct membranous envelope, he places the locomotive and prehensile power, whilst in the soft endosarc he recognizes a loose movement of the organic particles on each other-i.e., a rolling movement. Carter also considers that the ectosarc is chemically as well as physiologically different from the endosarc, having found that the ectosarc turns purple on application of iodine.

In fresh-water Amoeba, the inner sarcode is often, during forward movement, projected through the outer rind to its very edge. This is not the case with the land Amoebæ. The layer of ectosarc forming the boundary of the advancing mass shows a deep border of clear unwrinkled yielding sarcode, whilst the portion of ectosarc at the opposite side of the body is contracted into firm folds; the endosarc takes at first no active part in contraction, but is impelled forwards as the advancing front yields and spreads out. The ectosarc alone performs the functions of muscle-envelope, such as is seen in Mollusca. In comparison, therefore, with the sarcode of the water Amobæ, this ectosarc shows an advance in special function approaching that of muscle.

Is this enveloping ectosarc invested with membrane? Greef maintains that it is not, and further that its inner surface or border is not sharply defined, or separated from the inner sarcode. The lines and folds seen on the exterior are occasioned by the compression resulting from the construction of the ectosarc, which Greef conceives to have acquired a muscular character, though not strictly possessing the appearance of a muscle substance. The reactions of acids, alkalies, iodine, &c., do not indicate the existence of any membrane. The inner mass is a granular, soft protoplasm, not contractile. In it are seen transparent vacuoles, either in bubbles or cavities filled with fluid. These are of various size, and change place quickly under pressure of contractile action. They sometimes run together, forming a large bubble, at other times break up into a number of smaller ones. When the creature is motionless, a large bubble will slowly work its way to the periphery, then break into a group of smaller vesicles which gradually unite again into a bubble of the original size. They can, therefore, have no membranous wall, and are not contractile.

In the endosarc are found other contents—diatoms and algæ, taken in as food. Besides these there are seen highly-coloured yellow or brown particles which have often a distinct form, and contain a distinct nucleus. Sometimes these particles are agglomerated together, and the whole group is surrounded by a clear space. Sometimes a diatom or alga is included. Greef thinks these coloured particles subservient to digestion of food, and compares them with the yellow cell-like bodies of many lower animals (so-called liver cells)—in any case they are not a portion of the reproductive system.

Other crystalline particles are also seen, which Greef considers to be excretion. Auerbach, Wallich, Carter, and others, have seen the same kind of particles in all Amoeba and certain Rhizopods. Proceedings of the Bristol Naturalists' Society, vol. iv. part 2.