. Chimæroid fishes and their development. Fishes; Chimaeridae. I30 FISHES AND THEIR DEVELOPMENT. young sharks, save that, as in the case of man}' other chimreroid structures, the rate of growth is accelerated; the lateral-fold beginnings extend over fewer body segments and are higher (proximo-distally), leading us to conclude that in this mode of early fin growth the Chimseroid exhibits the same relation to the shark that the tel- eost bears to the ganoid. Especially convincing evidence as to the modified nature of the chimaeroid fin is produced by the development of the ventral &q
. Chimæroid fishes and their development. Fishes; Chimaeridae. I30 FISHES AND THEIR DEVELOPMENT. young sharks, save that, as in the case of man}' other chimreroid structures, the rate of growth is accelerated; the lateral-fold beginnings extend over fewer body segments and are higher (proximo-distally), leading us to conclude that in this mode of early fin growth the Chimseroid exhibits the same relation to the shark that the tel- eost bears to the ganoid. Especially convincing evidence as to the modified nature of the chimaeroid fin is produced by the development of the ventral "claspers"; for these, the antero-ventral hooks and the mixipterygia, are to be regarded as highly modified radials. The antero-ventral clasper, it is clear, has not j^et been evolved in the sharks, unless the greatly enlarged anterior lappet of the ventral fin be regarded as its equivalent; but there is good foundation for the belief that in Chimseroids between the antero-ventral organ and the compressed lappet of the B. 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
