36 Batrachia of the Permian Period of North America. [Januaty, ) 
ANISODEXIS Cope. 
This genus differs from those previously described, in the ine- 
quality in the sizes of the teeth of the external series. Thus 1n 
the upper jaw there is a very large one in the position of a canine, 
and in the lower jaw there are some large ones near the symphy- 
sis. The neural arch of the vertebrae resembles that of the 
genus Acheloma. The A. imbricarius Cope, is the only know 
species, and is represented in collections by fragments only. 
The size of its skull is nearly that of the Æryops megacephalus 
The sculpture of the superior surface of the skull is a coarse 
reticulation ; that of the sides of the jaws is of an imbricate of 
shingle-like character, The limbs are unknown. The vertebré 
do not exhibit an expansion of the summit of the neural spine. 
From the Texas beds. 
ZATRACHYS Cope. 
This genus was originally represented by a maxillary boa : 
which supports teeth of equal length, and whose surface is exti 
ordinarily rugose. In the typical species, Z. serratus, the rugost 
ties project in the form of teeth along the external alveolar bor 
der. Individuals with sculptured neural spines and dermal bone | 
are referred here. The intercentra are much like those of Eryop’ | 
and Acheloma, z! 
Two species are known, Z. serratus Cope, from Texas and a 
apicalis from New Mexico. In the latter the neural spines hav 
much expanded apices, with sculptured superior surfaces. at 
animal may have been four or five feet in length, while the r 
serratus could not have exceeded three feet. Both species er 
well protected from the assaults of the cotemporary carnivori 
saurians by their dermoössifications. 
3 
EMBOLOMERI. 
I proposed this order in 1880! to receive the family of a 
journal? and elsewhere, by the complete development of its ca 
and intercentra, both of which form entire vertebral bodies W i 
in pairs support single neural arches. No such character Is 
been detected in the known divisions of the Stegocephali. © 
1 AMERICAN NATURALIST, p. 610, is hee. r i 
? Loc. cit. 1876, p. 405; 1878. p. 319. Proceedings Am, Philos, S0C., rhe i 
as poe) 
