THP: 15ATRACIIIA OF NORTH AMERICA. 



Nearctlc localities. 



381 



Catalogue 

 number. 



No. of 



spec. 



Locality. 



When 

 collected. 



From -whom received. 



Nature of 

 specimen. 





1 

 1 

 1 







Capt. Stewart Van Vliet . . . 

 I. H. Clark 













3259 



llolotes Tex . 



















Neoiropical localities. 



Mirador, Vera Cruz 



Orizaba, Ea.st Mexico . - . 

 Guadalaxara, West Mox 

 Colima, West Mexico . . . 



Omoa, Honduras 



Yucatan 



Dr. C. Sartoiius . . 

 V. Suniiohraat. ... 



T. T. Major 



Jolm Xantus 



Dr. J. Xi. Lo Conto 

 Artlitir Sohott . ... 



AMPHIGNATHODONTID^. 



Bouleuger, Cat. Btitr. Sal. Brit. Mas., ed. u, 1882, p. 449. 



But two genera of this family are known, as follows : 



Digits with large dilatatious ou the extremities ; a dorsal dermal pouch ; 



Am2)]ii(jnatkodon Boul. 

 Digits acute at end; no dorsal pouch .Gri/inscus* Cope. 



The typical genns is hyl?eform, while Grypiscus is a robust terrestrial 

 type. The true position of the latter being somewhat doubtful, I give 

 the following more exact dehuition : 



Mandible with a series of caducous pleurodont teeth, and a permanent 

 elevated tooth on each side the symphysis. Prefrontal bones fully de- 

 veloped, in contact with each other throughout, and with frontoparietals. 

 Auditory apparatus well developed j tongue broad, entire, little free. 

 Vomerine teeth 5 no i^arotoid glands. (See Plate 68, fig. 11.) 



The mandibular teeth are obtuse, and scarcely project above the al- 

 veolar margin ; their attachment appears to be to the mucous membrane 

 only, on which account they are readily scraped away. 



The affinities of this genus are as yet obscure ; the mandibular teeth 

 and general form would refer it to the Hemiphractida?, but the form of 

 the sacrum separates it. The form of the cranium, with its broad out- 

 line and narrow brain-case, and of the body in general, are nearest to 

 Cyclorhamphus and Cophseus, though the form of the sacrum separates 

 it again. If referred to the Pelodytidre, it will be the type of a group 

 in the family characterized as follows : 



Frontoparietal bones fully developed; xiphisternum an emarginate, 

 cartilaginous shield; coccygeal style attached to two condyles; toes 

 webbed. 



"A figure of Gri/2)isciis unibrliuts will be found iu the Addenda. 



