474 Revieivti — Permo- Carboniferous Fauna, Bohemia. 



la 1860 only thirteen species of vertebrates were known from. 

 these formations in Bohemia ; now 123 species have been recorded^ 

 and Q& of invertebrates, making together 189 species, all figured 

 and described. 



In monographing and carefully drawing more than sixty species 

 of Stegocephalia, the author has been cautious not to advance any 

 phylogenetio speculations, seeing that the group does not lend much 

 help in explaining the evolution of amphibians, and we are led to 

 the conclusion that a long series of unknown vertebrates must have 

 existed before these formations were deposited — the ancestors, in 

 fact, of these Permian forms. 



The osteological details given in this work will certainly prove 

 of great value in future comparative anatomical investigations. 

 The beautifully preserved remains of Dipnoi, including even au 

 entire specimen, demonstrate how little that group has changed 

 from the Carboniferous Ctenodus to the living Ceratodus of Australia. 

 In the order Selachii the author has adduced important evidence as 

 to the structure of the fins in Pleur acanthus (XenacantJius) , and his 

 opinion that they have been developed from a series of parallel rays 

 has only a short time subsequently been confirmed by the discovery 

 of the fin of Cladoselache in the Upper Devonian of Ohio. Many 

 figures from this work have been reproduced by Wiedersheim and 

 other authors who have written lately on the fins of recent Selachii. 

 The tribe of Acanthodians has been augmented by two new and 

 important genera — Traquairia and Protacantliodes, which latter is 

 a predecessor of the true Acanthodians of later times. The notes 

 on Silurian Acanthodians are very interesting and most valuable. 

 Amongst the Palasoniscidee, the new genus Trissolepis, with thre& 

 kinds of scales, is most remarkable, showing the gradual development 

 of the ganoid scales beginning near the tail. 



In the fourth volume, which is devoted to the Invertebrata,. 

 evidence is brought forward to show that insects with complete 

 metamorphosis were already represented in Palasozoic times by the 

 Trichopteroid genus Phryancsa and by the larva of a beetle (Archi- 

 carabides pater). The myriopods, of which thirty-five species have 

 been recorded, are treated with especial care, being represented in 

 Permian times by a greater number of distinct families than at the 

 present day. The discovery that they possessed three simple thoracic 

 segments is very important. The Arachnida were represented by 

 Tetrapneumonous spiders, and the Merostomata by Prcelimulus Wood- 

 wardi, a Limulus with simple extremities to its legs. The Entomostraca 

 have long been determined with the valuable assistance of Professor 

 T. Eupert Jones, and the plates show that in some specimens the 

 soft parts and internal structures of the animal have been preserved 

 within the test, and even embryos. To the systematic worker in 

 the Malacostraca the restored figure of Gampsonyx from Lebach will 

 be of the greatest interest, as it shows that this Crustacean was not 

 provided with bifurcated appendages, like Mysis, but with simple 

 ones. A new genus of Crustaceans, Gasocans (a rather barbai'ous 

 name), has also seven equal pairs of simple legs, and forms with 



