which resemble one another so closely, growing as branches from the same stem. in habit and appearance as to be at first Now, as was long since laid down by sight hardly distinguishable. Edward Forbes, species which have a Supposing species to be constant, this singu-wide area of space-distribution, have a lar chain of resemblances would indicate similarly prolonged distribution in time; simply the special creation on the two sides of their capacity of adaptation to change of the Isthmus of two groups of species closely conditions operating equally in both resembling one another, because the circum-cases. And it is just where this capacity stances under which they were placed were so of adaptation is the greatest, that deparsimilar; but admitting "descent with modifi-tures from the primitive type show themcation," while gladly availing ourselves of the selves most strongly; such departures convenient term "representation," we at once (which often come to be so fixed and concome to the conclusion that these nearly stant that they might well be accounted allied "representative species" must have descended from a common stock, and we look specific characters) being simply the refor the cause of their divergence. Now, on sults of the pliancy of the organism, examining the Isthmus of Panama, we find which can adapt itself to changes of exthat a portion of it consists of Cretaceous beds, ternal conditions, instead of succumbing containing fossils undistinguishable from fos-to them. sils from the Cretaceous beds of Europe; the Isthmus must therefore have been raised into dry land in Tertiary or Post-tertiary times. It is difficult to doubt that the rising of this natural barrier isolated two portions of a shallow water fauna which have since slightly diverged under rather different conditions. I quote Alexander Agassiz: "The question naturally arises, have we not in different fauna on both sides of the Isthmus a standard by which to measure the changes which these species have undergone since the raising of the Isthmus of Panama and the isolation of the two fauna?" (p. 14.)

Keeping this principle in view, we now proceed to those yet more remarkable cases, in which types of animal life, which were characteristic of former geological periods, and which, from not occurring in shallow waters, were supposed to have altogether died out, have been discovered to be still holding their ground in the deep sea. Mention has been already made of this in the case of certain Tertiary shells; but there are other cases even more striking. The deep-sea explorations of our own countrymen may indeed be said to have originated in the disFew zoologists, we apprehend, will covery, by M. Sars junior (son of the late now dissent from this conclusion; for it eminent Professor of Zoology at Chrisis a principle accepted by all philosoph- tiana, and himself Inspector of Fisheries ical naturalists, that the more extensive to the Swedish Government), at a depth the range of comparison, the wider is of nearly 400 fathoms, off the Lofoden found to be the range of variation of spe- Islands, of a small crinoid, differing in cific types; so that forms which might the most marked manner from any crinoid be supposed to have had an originally known to exist at the present time, but distinct parentage, if only their most dif- clearly belonging to the Apiocrinite famferentiated types be compared, are found,ily, which flourished in the Oolitic period, by the gradational character which shows the large pear-encrinite of the Bradford itself when the comparison is instituted Clay being its most characteristic repreamong a large number of intermediate sentative, while the Bourgueticrinus of types, to be genetically identical. Nu- the Chalk seemed to be its latest. To merous instances of this kind have pre- Professor Wyville Thomson and Dr. sented themselves in the study of the Carpenter, who had been conjointly makPorcupine dredgings. Thus certain sea- ing a special study of this group, it was urchins of the Northern seas and of the clear that the little Rhizocrinus of ProMediterranean, which have been account-fessor Sars was a dwarfed and deformed ed as belonging to distinct species, were representative of the Apiocrinite type, found by Professor Wyville Thomson to which might be fairly regarded as a debe so gradationally connected with each generate descendant of the old pear-enother by the intermediate forms dredged crinite; and this encouraged them in the along the West of Ireland, the Bay of belief, on which they based their appliBiscay, and the coast of Portugal, that cation for Government aid, that a large the specific distinction altogether breaks number of such ancient types might down. And Professor Duncan, who has probably be found, by carrying down the examined the corals, has found not only exploration of the bottom by the dredge reputed species, but reputed genera, to to a depth not previously thus exambe specifically identical; the two forms lined. This expectation was fully justi

fied by the result. For in their first | absolute continuation, of the Cretaceous; (Lightning) cruise they not only found the deposit of globigerina-mud over that that the layer of globigerina-mud, pre- area having never been interrupted durviously brought up by the sounding-line ing the whole of the Tertiary period. from the surface of the sea-bed, has a The physical grounds for the belief that thickness to which no limit can be as- there has been no such change in the signed, and that in every particular the Atlantic basin during the whole of that whole mass resembles chalk in the pro- period, as would have converted its botcess of formation, as had been previously tom into dry land, have been already stated by Bailey (U.S.), Huxley, Wallich, pointed out (p. 776); and if it has remained and others, in regard to the small sam- a deep-ocean basin during that time, it is ples they examined; but they further obvious that while an interrupted sucdiscovered that this bears on its surface cession of Tertiary deposits, imbedding a number of types of animals whose facies terrestrial, fresh-water, estuarine, and is essentially that of the Cretaceous pe- shallow-water marine faunæ, was formed riod. The most remarkable of these was on the borders of that basin, where slight a beautiful siliceous sponge, so closely differences of level would alter the whole corresponding in general structure with distribution of land and sea, an unbroken the ventriculites of the Chalk, that no series of layers of a substance resembling doubt could be entertained of the inti- the old Chalk in every essential particumacy of their relationship. The interest lar, would have been formed by the conexcited among zoologists and palæontol- tinued activity of protozoic life over the ogists by this discovery, powerfully rein- newest beds of what we are accustomed forced that which had been called forth to call the "Cretaceous formation," enamong physicists and physical geogra- tombing a deep-sea fauna, which would phers by the temperature-observations preserve the general facies of the Cretataken during the same cruise; and this ceous, whilst differing from it in detail, was fully sustained by the discoveries of as that of the upper beds of our Chalk the next year. For the number of Echi- formation differs from that of the lower. nidan forms, peculiarly characteristic of By Sir Charles Lyell it is maintained that the old Chalk, that were met with in the we must regard the Cretaceous period Porcupine cruises of 1869-several of as having come to an end with the elevawhich are described and beautifully fig-tion of the Chalk of Europe, and with the ured in Professor Wyville Thomson's disappearance of the higher types of the pages surpassed all expectation; and Cretaceous fauna, such as its charactersome of these, as the singular" chain-istic fishes and chambered Cephalopods. mail" urchin Calveria hystrix, perpetuate But Mr. Prestwich has supplied an adespecial Cretaceous types, which were sup-quate vera causa for this extinction, in posed to have long since died out. The the establishment at this period of a free results of the dredgings simultaneously communication between the Polar area carried on by Count Pourtales in the Florida Channel, have proved singularly accordant in this particular with those obtained by our British explorers; the general character of the Echinoderm fauna there met with, bearing a singular resemblance to that of the old Chalk, although without any identity of species; and the Ananchytes, one of the commonest of the Cretaceous urchins, whose type had been regarded as altogether extinct, being distinctly represented by the newly-in structure), and would in turn leave discovered form (also included in the Porcupine collection) which Mr. Alexander Agassiz has described under the name Pourtalesia.

and the Cretaceous sea, which he regards (on quite independent grounds) as having been previously cut off from it by an intervening continent. The reduction of temperature thus produced would have killed off all the inhabitants of the upper waters which were dependent on a warmth approaching the tropical; whilst those which could adapt themselves to the change would have maintained their ground (with more or less of modification

their remains to be entombed in the everaccumulating mass of globigerina-mud. That scarcely any of the molluscs, echinoderms, or corals of the present deposit These facts afford a most remarkable can be specifically identified with those of confirmation to the doctrine of Professor the old Chalk, is exactly (as is justly reWyville Thomson, propounded in Dr. marked by Professsor Wyville Thomson) Carpenter's first report,- that the forma- what might be fairly expected, in contion now going on upon the North At-sideration of the various changes which lantic sea-bed is not a repetition, but an 'must have occurred since the commence

ment of the Tertiary epoch, in the vari- Carpenter presented to the public the reous conditions of their existence. "The sults of the tentative Lightning cruise of utmost which can be expected is the per- the previous year : sistence of some of the old generic types, with such a resemblance between the two fauna as to justify the opinion that, making due allowance for emigration, immigration, and extermination, the later fauna bears to the earlier the relation of descent with extreme modification."

For,

still more the speculations which I have venThe facts I have now brought before you tured to connect with them, may seem to unsettle much that has been generally accredited in geological science, and thus to diminish rather than to augment our scock of positive knowledge; but this is the necessary result of We must content ourselves with indi- the introduction of a new idea into any decating another very important bearing partment of scientific inquiry. Like the flood which these deep-sea researches must which tests the security of every foundation have upon geological theory - the modi- that stands in the way of its onward rush, fication they necessitate of the glacial but leaving unharmed the edifice which rests overthrowing the house built only on the sand, doctrine. For it now becomes obvious, secure on the solid rock, so does a new as Dr. Carpenter pointed out in his sec- method of research, a new series of facts, or a ond report, that as the climate of the sea- new application of facts previously known, bottom has no relation whatever to that come to bear with impetuous force on a whole of the land (a glacial temperature now fabric of doctrine, and subject it to an underprevailing over the Equatorial sea-bed), mining power which nothing can resist, save the presence of Arctic types in any ma- that which rests on the solid rock of truth. rine formation can no longer be accepted And it is here that the moral value of scientific as furnishing evidence per se of the gen- study, pursued in a spirit worthy of its elevated aims, pre-eminently shows itself. eral extension of glacial action into temperate or tropical regions. If, as Dr. ble contrast between the "trader in science" as was grandly said by Schiller in his admiraCarpenter maintains, the underflow of and the "true philosopher," - "New discovPolar water towards the Equator is sus-eries in the field of his activity which depress tained by the disturbance of equilibrium the one enrapture the other. Perhaps they produced by thermal agency alone, then fill a chasm which the growth of his ideas had such an underflow must have taken place in all geological periods, provided that there existed a free and deep communiation between the Polar and the Equatorial areas. By Professor Wyville Thomson, on the other hand, it is main-nature, a newly discovered law in the physical world, overthrow the whole fabric of his tained that the Polar underflow is the re- knowledge, he has always loved truth better sult of the deflection of the Equatorial than his system, and gladly will he exchange current, by the opposition of land, north- her old and defective form for a new and wards and southwards, so as to occasion fairer one." an indraught which this underflow tends to fill; and on this hypothesis, if there were a free passage for the Equatorial current through Central America into the Pacific, as there would be no Gulf Stream, there would be no Polar underflow; so that in any former geological period in which any such conditions may have existed, the temperature of the Equatorial sea-bottom would not have been depressed, however free may have been its communication with the Polar areas. This is tantamount to saying that an enormous disturbance of fluid equilibrium must have been constantly in existence, without producing any move ment - a proposition which no mechanical philosopher can accept.

We cannot more appropriately conclude this exposition, than by the following citation from the lecture at the Royal Institution (April 9, 1869), in which Dr.

rendered more wide and unseemly; or they place the last stone, the only one wanting to the completion of the structure of his ideas. should a new series of ideas, a new aspect of But even should they shiver it into ruins,

From Chambers' Journal. THE MANOR-HOUSE AT MILFORD.

CHAPTER IX.

'Tis better to be vile than vile esteemed.

FREWEN wildly raged when he heard of Tom Rapley's misfortune, and his own involvement as surety, denounced his folly in doing a good turn for any one, and would not hear of any suggestion that, after all, it was possible Tom had been really robbed. He caused Tom to be brought before him in his private office, and spoke to him in a terrible voice. He would listen to no excuse or explanation. "Find that money, sir, by four o'clock to-day, or to prison you go."

"Of course, I believe you, Tom. Do you mean to say that anybody suspects you?"

"Everybody does."

"Then you must shew everybody he is a slanderer. Who can have taken the money?"

"There was a pedler who slept in the old barn last night, and yes, there is possibly Skim, who doesn't bear a very good character."

And the lawyer was not indulging in a with knitted brows. "Is there anybody vain threat. There was a meeting of whom you can suspect?" she said. magistrates that day at Biscopham. Mr. "Then you believe me?" cried Tom. Frewen, who attended there in his capa-"You don't think, as other people do, city of clerk to the bench, mentioned to that I've taken the money myself?" them the apprehended defalcation at Milford. At his request, they signed a warrant of commitment, to be executed if the money were not paid over before the bank closed. With knowledge of this in their minds, the police were not likely to exert themselves strenuously to find out the alleged robber of Tom Rapley's gold. The superintendent, indeed, took down from his lips a statement of the circumstances under which he lost the money. But when Tom came to describe the place where he had hidden the gold, he hesitated, and gave a very vague account of it. For it occurred to him all of a moment: "If this money is really gone, and I go to prison, it will be a bit of comfort to know that Lizzie has a roof over her head, and ten shillings a week to keep her from starvation." Now, if he disclosed the fact, that he had been roaming about in the empty house, and that they had broken an entrance into it, Frewen would assuredly turn them all out without the shortest respite. The practised ear of the police-officer detected the doubt and equivocation in Tom's narrative.

Something in the man's manner told Tom what he really meant that they would have Tom himself in custody ere night. He had been experiencing that hard incredulous manner all the morning, and had accustomed himself to look for suspicion, till at last he almost imagined that he must really be the rogue that everybody persisted in believing him. There was only one person in the whole of Biscopham to whom he could go with any hope of having his story credited, or gaining any sympathy, and that was Emily Collop.

"Skim, yes; I know him," cried Emily; "he often comes to see father. But it couldn't be Skim. Why, he was with father last night."

All on a sudden the thought struck her of her father's lengthened absence the night before, and of his coming home with gold, too, that she had still about her person. She felt all over her a cold shudder. Where did her father go with Skim?

"Could you identify any of that money, Tom?"

66

"No; how could I? Sovereigns are sovereigns, as like one another as peas." "And what will happen to you, Tom, you don't get the money back?" "I shall go to prison. Frewen has got a warrant against me already."

if

"Oh! that's dreadful," said Emily shuddering. "To go to prison like a criminal because you've the misfortune to lose some money! Wait! I hear father; he's just come in. I'll call him."

Collop came in, looking pale and distraught. "Do you know what's happened to Tom?" cried his daughter. "I've heard something about it," said Collop, head. shaking his "Oh! Thomas, what would your Aunt Betsy have said if she'd seen you in such a predicament? ?"

"Tell father how it happened," said Emily.

Tom began the story once more. When he came to speak about hiding the money in the kitchen of the deserted house for he thought he was safe in being candid with Collop and his daughter-the worthy draper trembled all over, drops of perspiration started from To Collop's shop he went, and into the his forehead, and concealed the working little low-pitched room over the shop, of the lower part of his face with his redolent of corduroys and fustians. hand. Emily watched them both narEmily hadn't heard the story as yet. rowly, casting quick searching glances Tom told her the whole, and she listened at each alternately. But when Tom went