372 



PALEOZOIC TIME. 



Characteristic Species. 



1. Radiates. — ( a .) Polyps. — Cyathophylloid Corals, (b.) Acalephs. — Corals of 

 the genus Stenopora. (c.) Echinoderms. — Crinoids near Cyathocr'mus ; Echinoids of 

 the genus Eocidaris, near the Paleozoic Archceocidaris. 



2. Mollusks. — (a.) Bryozoa'ns. — Fenestella retiformis Vcrn., found in the Per- 

 mian of Russia, England, and Germany, besides a dozen other related species. 



(b.) Brachiopods. — Spirifer alatus Schloth., from England, Lower Zechstein in Sax- 

 ony, — some specimens 2\ in. broad; SpirifeHna cristata Dav., from the Zechstein, 

 Germany; Productus horridus Sow., from England and Germany, characteristic par- 

 ticularly of the Lower Zechstein, and occurring also in the Kupferschiefer; Strophalosia 

 excavata Gein , England, Germany; the species of the genera Productus And. Stropha- 

 losia are exceedingly abundant in individuals ; Camarophoria Schlotheimi Von Buch, 

 from Russia, Germany, and England; the genus is related to Terebratula and Pen- 

 tamerus, and is peculiar to the Carboniferous and Permian; Camarophoria superstes, 

 Russia. 



(c.) Lamellibranchs. — Pseudomonotis speluncaria Beyr., England, Russia, and Ger- 

 many in the Lower Zechstein ; Clidophorus Pallasi Gein., Russia and Germany; My a- 

 Una squamosa Sedg., Russia, England; Avicula KazanensisYem., Russia; Bakewellia 

 antiqua King, England, Russia, Germany; Schizodus dubius M., a very common species 

 in England, Germany, and Russia; Schizodus Schloiheimii Gein., S. obscurus Sow., and 

 S. truncatus King. The genus Schizodus is of the same family with Trigonia, a charac- 

 teristic genus in the Reptilian age : it commenced in the Devonian. 



(d.) Gasteropods are rare fossils in the Permian. There are a few species of Murchi- 

 sonia and Straparollus, Paleozoic genera, besides some others. 



(e.) Pteropods of the genera Theca and Conularia. 



(/•) Cephalopods existed, and among them two or three species of Orthoceras. 



3. Articulates. — No Trilobites are known. Ostracoids are common. Under 

 Tetradecapods, occurs here the Amphipod, Prosojjoniscus problematicus, from the Per- 

 mian of Durham, England, first described by Schlotheim, but recently explained by 

 Bates. Decapods of the order of Macrourans appear to have commenced in the Coal 

 formation. But the first of the Brachyurans is announced from the Permian by Von 

 Schauroth, who names it Hemitrochiscus paradoxus. It is an eighth of an inch long. 

 Geinitz regards it as related to the Pinnotheres family. 



4. Vertebrates. — (a.) Fishes. — Eig 696, Palazoniscus Freieslebeni Agassiz, one- 

 third the natural size; common in the Kupferschiefer, and also found in the Coal- 

 measures in England, at Ardwick. Over forty species of fishes have been described. 

 The more characteristic genera are Palceoniscus, Platysomus, Acrolepis, Pygopterus, and 

 Xenacanthus, but they are also all Carboniferous. Besides the above, the species include 

 Palceoniscus elegans Sedgw., P. comptus Ag., Platysomus macrurus Ag., PL gibbosus Bl., 

 Acrolepis Sedgwickii Ag., Pygopterus mandibularis Ag., Ccslacanthus granulatus Ag., etc. 

 Janassa bituminosa Mtinst. and Wodnika striatula Miinst. are species of Cestraciont 

 sharks from the Kupferschiefer. Menaspis armata Ewald, from the Kupferschiefer, 

 has been regarded as a Cephalaspid related to Pteraspis, but also as the head or tail 

 shield of a Crustacean. 



(&.) Amphibians, Reptiles. — A number of Labyrinthodonts have been described, and 

 also Reptiles of the tribes of Lacertians and Theriodonts. Fig. 697 represents one 

 of the Permian Lizards, Proterosaurus Speneri Meyer ; it was 3ifeet long, and is from 

 the copper-slate (Kupferschiefer) of Germany and Saxony. Two other species have 

 been found at Durham, England, along with Labyrinthodonts. Dasyceps Bucklandi 

 Huxley is a Labyrinthodont, from Kenilworth, England, the specimen a cranium 

 10 inches long and 9\ broad. See, further, the note on page 851. 



These Permian Lizards had biconcave vertebrae,like the inferior swimming reptiles, 

 but the socket teeth of the Crocodile?. The teeth were flattened,and crenulate at the 



