. Dansk botanisk arkiv. Plants; Plants -- Denmark. F. Børgesen: Rhodophyceæ of the Danish W. Indies. 23 3. Acrochætium pulchellum nov. spec. Thallus minutus, pulviriatus. Pars basalis e filis repentibus ramosis, in parte centrali sensim confluentibus, composita. Spora germinans in duas cellulas fere æquales di visa est, quarum utra- que filum ramosum repens procreat. Gellulæ in parte basali irreguläres, breves, 7—10/^ longæ et o—Qfi latæ. Ex his cellulis fila erecta brevia, 1—3 raro plures cellulas continentia, ca. 24/i alta, egrediuntur ; cellulæ b—Qfx latæ, diametro IV2—2-plo longiores, chro
. Dansk botanisk arkiv. Plants; Plants -- Denmark. F. Børgesen: Rhodophyceæ of the Danish W. Indies. 23 3. Acrochætium pulchellum nov. spec. Thallus minutus, pulviriatus. Pars basalis e filis repentibus ramosis, in parte centrali sensim confluentibus, composita. Spora germinans in duas cellulas fere æquales di visa est, quarum utra- que filum ramosum repens procreat. Gellulæ in parte basali irreguläres, breves, 7—10/^ longæ et o—Qfi latæ. Ex his cellulis fila erecta brevia, 1—3 raro plures cellulas continentia, ca. 24/i alta, egrediuntur ; cellulæ b—Qfx latæ, diametro IV2—2-plo longiores, chromatophorum stellare pyrenoide centrali instructum continentes. Pili hyalini terminales, ca. 100 /i longi, 2—3 // lati, numerosi. Sporangia in filis erectis terminalia, raro in filamentis repentibus sessilia, ovata, 5—1 (x lata et 9—10// longa. Of the species described by Rosenvinge the present plant seems to come nearest to Acr. (Chr.) hiimile; in its mode of growth and the structure of the cells it also some- what resembles A. (C.) polyblastam Rosenv. but the erect filaments are not so large. In agreement with the above mentioned species the germinating spores are divided pig. 14. Acrochætium into two nearly equal cells (Fig. 14); in the ^",^^^4";Ent"37„\Xch young plants these cells are easily recogniz- the original spores, di- able, in the older they are most often not. vided into two cells, ' , „ . „, . are yet visible. From each of these cells a creepmg filament (About 600:1). is given off in opposite directions; these filaments soon begin to branch, the branches in the middle fusing more or less together. By this method of growing a relatively large disc may be formed (Fig. 15). The cells are rather irre- gularly shaped with more or less sinuated walls, short, about 5—6// broad and 7—10// long. From the cells in the basal layer short erect filaments con- sisting of 1—3 seldom more cells arise. These filaments are termin
Size: 1197px × 2089px
Photo credit: © Paul Fearn / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookcollectio, bookdecade1910, booksubjectplants
