regulariter et distincte septatis, olivaceo-flavis, asperulis vestitis; pilis terminalibus olivaceo-flavis, regulariter septatis, asperulis vestitis, arcuatis, apice subrectis vel incurvatis; ascis clavatis, octosporis, 42 X 10 μ, p. sporif. 26 μ; sporidiis olivaceo-brunneis, irregulariter ovatis, utrinque apiculatis, 9.8 × 5.4 μ (9.4-11 × 4.7–5.6). On paper, dung and other materials of various kinds from New England. In cultures of old paper from Java (R. Thaxter). The small size and characteristic golden yellow color clearly distinguish this species from all others except Chaetomium trilaterale and Chaetomium fusiforme. From the former of these it differs in that the spores are discharged in long black cirrhi, in the comparative obscurity of the perithecial hairs at maturity, in the incurved tips of the terminal hairs, and in the irregular, oval shape of its spores. From the latter it differs also in producing long black cirrhi, in the incurved extremities of its terminal hairs, and in the size of its spores and their irregular oval shape. Chaetomium fusiforme, sp. nov. Griseum vel pallide olivaceum. Peritheciis minutis, subglobosis, 120 X 102μ (116-123 X 101-125), cirrhis carentibus; pilis lateralibus numerosis, tenuibus, flexuosis, regulariter et distincte septatis, olivaceo-flavis, asperulis vestitus; pilis terminalibus crassioribus, asperulis vestitis, olivaceo-brunneis, regulariter et distincte septatis, arcuatis, apice circinantibus vel subconvolutis; ascis clavatis, octosporis, 48 X 11 μ, p. sporif. 32 μ; sporidiis laete olivaceo-flavis, vel olivaceo-brunneis, longis, angustis, subfusiformibus, apice rotundatis vel apiculatis, 15.8 × 5.4 μ (15-16 × 4.8–5). μ On paper from Alabama (Herb. R. Thaxter). The long narrow spores distinguish this form from all other species of Chaetomium. In general characteristics it most nearly resembles Chaetomium aureum and Chaetomium trilaterale, but differs from both in the long, slender, fusiform spores. Chaetomium trilaterale, sp. nov. Olivaceo-flavum. Peritheciis minutis, subglobosis, 106 X 94 μ (100-110 X 90-97), cirrhis carentibus; pilis lateralibus numerosis, gracilibus, longioribus, regulariter et distincte septatis, aureo-flavis, basi rectis, asperulis vestitis, apice 1-3 spiraliter convolutis, levibus; pilis terminalibus irregulariter septatis, olivaceo-brunneis, asperulis vestitis, arcuatis, apice 1-3 spiraliter convolutis; ascis clavatis, octosporis, 50 X 9.5 μ, p. sporif. 26 μ; sporidiis subdistichis, laete olivaceo-flavis, forma sphaerasectoris praeditis, utrinque subapiculatis, 9.5 X 5.5 μ (8.9-9.7 × 5.2-6). On paper from New England (Herb. R. Thaxter). This species has certain characteristics in common with Chaetomium aureum and Chaetomium fusiforme. 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