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Fossil Forms

teeth, species, fishes, figure and lower

FOSSIL FORMS.

Our knowledge of the Sphynenidte far antedates the historic period; even Aristotle's mention of them is comparatively recent. In the Cre taceous seas which covered Kansas and the adjacent parts of the Great Plains region, and in the bays and shallow sounds along the North Carolina coast, there disported themselves in large numbers certain fishes of powerful frame and voracious habits to which the paleontologists have given the name Protosphyrcenidce, the first sphyrtenas. The generic name was assigned to these fishes by Leidy as early as 1857, but it seems that Agassiz much earlier than this had examined the teeth of the same form and had erroneously placed their owners among the Saurocephali. There is, it must be confessed, some doubt about the affinities of these fishes. Indeed, Jordan (1905) says " the jaws are armed with very strong teeth, as in the barracuda, which however the species do not resemble in other respects." Two of these Protosphyrtena fish are known by the specific names of Protosphyrcena nitida and perniciosa. Careful perusal of the litera ture would probably give the names of a number of other species referable to this fossil genus. However, it is not the purpose of the present writer to go into the matter of fossil forms further than to call to the attention of the reader the fact that the fossil Protosphyrtenids are by many considered as the ancestors of the modern Sphyrtenids. So Felix (1890) seemed to think, and his figure of Protosphyrcena reproduced herein as figure 25, plate vn, certainly does show the head of a fish whose teeth and jaws are remarkably like those of the big barracuda. Attention is called to the two great canines in front and to the knife-shaped teeth of the upper and lower jaws. The teeth of the

upper jaw are seen outside those of the lower, but whether this is natural or an artifact can not be said—possibly both, and rather cer tainly the latter, since the great canines are also found outside the lower jaw-bone. However, from the drawing they seem to be rooted in the premaxillary.

Louis Agassiz (1843) also figures in the atlas to volume v of his great work on fossil fishes two skeletons of certain fishes which he does not hesitate to call Sphyrcena. These skeletons are from the Eocene of Monte Bolce in Italy. The first is called S. bok,ensis, from its place of discovery, and is based on a number of skeletons from different muse ums. The second is S. gracilis and several specimens are known. These are reproduced herein as figures 23 and 24, plate vu. Attention is Galled to the shape of the snout and to the upper teeth in figure 24, and to the 24 vertebrae (the proper number) in figure 23.

In 1901, the distinguished paleontologist Dr. A. S. Woodward catalogued the Sphyra3nid material in the British Museum and reduced most of the previously described forms to synonymy. He sets up three distinct species: Sphyrcena bokensis, intermedia, and suessi. Six other species are quoted from earlier writers, but Wood ward thinks the material from which they were described to be so imperfect (in one case consisting of a single tooth only) as not to justify the erection of species upon it. All the valid material is from the Eocene of Monte Bolce near Verona in northern Italy. Woodward throws out Agassiz's S. amid. from Mount Lebanon as not belonging to this genus.