Fauna of the Gas-coal etc., of Bohemia. 273 



Bicnodon Copei has four teeth in the preruaxillary bone ; they are 

 slender, with blunt crowns, furrowed, with a few vertical depi'essions. 

 The maxillary teeth are smaller. The madibular teeth are not half as 

 long as those in the maxillary. The pterygoid has a remarkable 

 sickle-shaped form. An internal process meets the expanded base of 

 the parasphenoid. The whole palatal curved portion of the pterygoid 

 is densely studded with small teeth like shagreen. The vomer is 

 probably similarly covered with teeth. In the vertebral column the 

 neural arch is united only to the anterior third or half of the centrum. 

 The ribs are hollow, three times as long as the vertebrge, and have 

 heads. The scales are much longer than the vertebrge, and are 

 mostly about three millimetres in length. They are very finely ribbed 

 and somewhat granulated towards the extremity. 



Bicnodon disperans is distinguished from the preceding species 

 chiefly by the scales, which have the hinder border thickened and 

 serrated. The furrowed extremities of the premaxillary teeth are 

 like those of the foregoing species. Bicnodon trachylepis has scales 

 similar to those of Bicnodon dispersus, but the smaller scales, regarded 

 as abdominal, are nearly square, and obliquely keeled, so that the 

 lesser portion is smooth and the large division tubercled. 



The genus Orthocosta is formed for an elongated slender amphibian 

 with unusually elevated spinous processes, which are constricted at 

 the base and expand in a fan-shape above. The ribs are slender 

 and short. The caudal vertebra are short, with well-developed 

 spinous processes ; the earlier vertebrEe carry ribs. The dorsal scales 

 are oval and sculptured. The abdominal scales are obliquely widened. 

 and thickened on the hinder border. Orthocosta microscopica is 

 founded on remains so minute that the entire animal could not have 

 exceeded 23 mm. in length ; yet all the parts are completely ossified. 

 The dorsal scales are as long as the vertebrae, ovate, ribbed ; the 

 ventral scales are transversely widened, and have the hinder margin 

 thickened like a rod. Twenty-one trunk vertebrje are preserved, 

 which agree in form with those of Hyloplesion. The neural arch 

 is higher than the centrum, and is limited to its anterior third. The 

 femur is three times as long as a dorsal vertebra. 



A lower jaw is refeiTcd from the character of the teeth to 

 Lepterpeton. 



The last family discussed in this part is the Microbrachida?, 

 represented by the genus Microhrachis and three species. These 

 animals have the body slender, with anterior limbs small, and cranial 

 bones sculptured with radiating and reticulate grooving. The 

 middle thoracic plate is broad with a long stalk. The abdominal 

 surface is defended with scales. 



Microhrachis PeliTcani has the upper bones of the skull marked 

 with radiating grooves which form a network. The body is slender, 

 with the tail half as long as the body and the anterior limbs very 

 small. The entire length is about 150 ram. The scales which were 

 of large size were sculptured much as in the preceding species. 



The orbits of the eyes are oval in the anterior third of the skull 



DECADE III. TOL. H. — NO. VI. 18 



