. Chimæroid fishes and their development. Fishes; Chimaeridae. â >'.. ? â â ''^'^'f-iX}-'- if^ w; â .^>-*«iv;rfi«i;ijc>^!c&i«?Ssca:«£iSt"^ m n Fig, 35.âSection of fertilization stage, showing near the surface and at the side of the germinal area a sperm which has just gained entrance. This is shown at 5, surrounded by a lighter area of germinal material. In the depression above the sperm is a mucus- like mass which may represent in part the tail of the sperm. ?/^/, Middle piece. X 575. Fig. 36.â^Section of fertilization stage, showing deep entrance pit of a s
. Chimæroid fishes and their development. Fishes; Chimaeridae. â >'.. ? â â ''^'^'f-iX}-'- if^ w; â .^>-*«iv;rfi«i;ijc>^!c&i«?Ssca:«£iSt"^ m n Fig, 35.âSection of fertilization stage, showing near the surface and at the side of the germinal area a sperm which has just gained entrance. This is shown at 5, surrounded by a lighter area of germinal material. In the depression above the sperm is a mucus- like mass which may represent in part the tail of the sperm. ?/^/, Middle piece. X 575. Fig. 36.â^Section of fertilization stage, showing deep entrance pit of a sperm. From the lowermost point arise branching rays. Fig. 37.âDetail of section of specimen shown in fig. 34. From the path of a sperm astral rays branch in many directions, and at various points (indicated by the dark points) new centers of radiation appear. Fig. 38. âDetail of fertilization stage shown in fig. 34. Tlie present section follows almost exactly the entrance path of a sperm. The latter appears at 5, and it is seen thai the entrance pit is a delicate tube extending downward in the direction of a sperm. Around the latter appears a well-marked asler, and in this neighborhood, strung along a prominent ray of the aster, are a number of deeply stained " ; A similar "cenlrosome" occurs near the lowermost point of the entrance tube of the sperm. forming a plug-shaped mass twice as deep as wide (fig. 34). This is possibly the homologue of the Panderian nucleus figured in the shark egg; certain it is, how- ever, that the egg of Chimaera has not as clearly a marked series of tunics in its yolk Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Dean, Bashford, 1867-1928. Washington, D. C. , Carnegie Institution of Washington
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectfishes, bookyear1906
