Revieics — Dr. Anton Fritsch — Fauna of the Gas-coal. 271 



II. — Fauna der Gaskohle und der Kalksteine der Perjifor- 

 MATioN BoHMENS. vuii Dr. Anton Fritsch. Band I. heft, 4. 

 (Prag, 1884.) 



Fauna of the Gas-Coal and Limestone of the Permian 

 Formation of Bohemia. 



THE fourth part of Dr. Fritsch's work completes the first volume, 

 which extends to 182 pages, illustrated with 116 figures printed 

 in the text, and 48 coloured plates. It is a work for which naturalists 

 will be grateful, and which has already won for its author the kindly 

 regard and esteem of all who are able to appreciate his labours. 

 Professor Fritsch begins with an account of the family Hyalonomidee, 

 which is made to include Dawson's genera Hyalonomus and Smiler- 

 peton; and four genera of the author's named Hyloplesion, Seeleya, 

 Orthocosta and Ricnodon, which are fully described. 



Hyloplesion is a slender lizard-shaped amphibian. Its skull is 

 broad, tapers anteriorly, and is rounded in front. The orbits for the 

 eyes ai"e placed anteriorly. The cranial bones are smooth, with a 

 few small scattered pits. The teeth ai'e small, slender, smooth, and 

 even. Traces of the gill arches are found. The thoracic vertebras 

 have the spinous processes expanded in longitudinal fans. The 

 ribs are curved, five times as long as the vertebrae, with both 

 capitulum and tuberculum. The whole body was sheathed in scales, 

 and on the abdomen these have a thickened posterior margin, but 

 are only one-third the size of those on the dorsal region. Prof. 

 Fritsch points out the resemblance of this type to Hyalonomus ; 

 but because that genus is at present so imperfectly known, and 

 the remains show some differences in the vertebrae, teeth, and other 

 organs, a new genus is founded. The only species is Hyloplesion 

 longicostatum. Its remains are recognized by the form of the scales, 

 vertebrae, and ribs. The ovate scales which are very small on the 

 somewhat short tail are distinguished by dichotomously branching 

 radiating ribbing. Scales appear to have covered the bones of 

 the skull. Those on the abdomen appear to have been subquadrate. 

 In the skull the parietal foramen is large, and placed toward the 

 anterior third of the large parietal bone which however is blended 

 with the frontal. The skeleton is well ossified. In the upper jaw 

 there ai"e about 13 teeth, of which the six in front are the largest. 

 The jaw is short and only extends under the eye. The skull bones, 

 however, are more or less scattered, and are described in detail. 



There are about thirtj^ vertebra anterior to the pelvis, and forty in 

 the tail. The notochord is continuous through the concave terminal 

 cups of the centrum. The zygapophyses are distinct in the earlier 

 vertebrge and the neural spine elongates lower down the back. The 

 sacral vertebrse have no distinctive characters. The caudal vertebrte 

 are short and wide, and have no ribs. The pectoral and pelvic 

 arches and limbs are imperfectly preserved. There were five digits, 

 terminating in clawed phalanges. 

 . The genus Seeleya is founded on a slender amphibian with a large 



