File:Popular science monthly (1872) (14766896835).jpg

Identifier: popularsciencemo27newyuoft (find matches)
Title: Popular science monthly
Year: 1872 (1870s)
Authors:
Subjects: Science
Publisher: New York : D. Appleton
Contributing Library: Gerstein - University of Toronto
Digitizing Sponsor: University of Toronto

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reathers in the water. Whatever we may call such changes, they areplainly a specialization which has carried them further and furtheraway from their starting-point; and, as in the case of the reptiles,this starting-point has been near to orders higher than itself. ThePermian Batrachia are nearer in structure to the Permian reptiles(Theromorpha) than any subsequent form of Batrachia has been(Fig. 3). Professor Agassiz pointed out that the early fishes presented rela-tions to other vertebrata, as I have since shown to be true of the Ba-trachia and Reptilia. Some of the primitive fishes he called sanroid or reptilian fishes. Batrachian fishes would have been a more accu- ORIGIN OF MAN ANB THE OTHER VERTEBRATES. 613 rate designation, for it is highly probable that it was from one of theearly orders of fishes that the Batrachia took their rise. Omitting fromconsideration the lowest vertebrata, the sand-lances and lampreys,which are not fishes, we have remaining a body of animals which pre-
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FiG. 3.—Skitll OP Ektops MBGACEPHALus. (Cope.) A Batrachian of the Permian period. Onefllftli natural size, upper side. (From Texas.) sent great varieties of structure. Of the four great sub-classes intowhich they naturally fall, but one can be called true fishes. The othersembrace the sharks, the chimaeras, and the lepidosirens. It is interest-ing to note that these four divisions are more closely approximatedduring the Permian period than at any later time. An order tech-nically referred to the sharks, and known as the Ichthyotomi, com-bines many of the characters found separately in three of the sub-classes. The creatures which especially deserve the name of batrachianfishes, the ceratodonts, etc, also abounded during the Permian period.From this time the true fishes began to run their course. They havepeopled all waters, and have branched into a greater diversity of form 6i4 THE POPULAR SCIENCE MONTHLY. than any of the other divisions of vertebrata. And paleontology andzoology s

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