GEOLOGICAL SURVEY OF THE TEEEITOEIES. 371 



existence. Imbedded in the same rock, in close proximity to tlie bones 

 of the skeleton, there was detected an isolated tooth, which is supposed 

 to belong to the same animal. The tooth is compressed conical, and 

 curved, and has its borders quite sharp. 



Since describing these remains, and referring them to an extinct genus 

 and species under the name of Saniva ensidens, in breaking open some 

 portions of the rock containing the remains of the skeleton, a fragment 

 of the upper jaw has been detected, evidently forming part of the latter. 

 The teeth contained in the fragment are imperfect, but are sufficiently \ 

 well preserved to indicate a shape different from the isolated tooth above 

 mentioned. Their form is more like those of the living Iguana, but they 

 are not serrated. The isolated tooth is like those of the Monitor. ISo 

 traces of scales were found imbedded in the rock in association with 'the 

 bones. 



Glyptosaurus, Marsli. 



During the last summer Dr. Carter sent to me a number of detached • 

 vertebrsB and fragments of other bones, found in the vicinity of Fort 

 Bridger, wliich resemble those of the skeleton of Saniva ensidens. These 

 were accompanied with a number of osseous scales, resembling those of 

 the living armadillos. Similar scales, from the same locality, have been 

 described by Professor Marsh, and referred to a lacertiliau with the 

 above name. From the difference in ornamentation of the scales and 

 other characters, the remains he attributed to four different species un- 

 der the following names : 



Glyptosaurus sylvestris. Glyptosaurus nodosus. Glyptosaurus ooellMus.' 



Glyptosaurus anceps. 



OPHIDIA. 



Among other reptilian remains obtained from the Tertiary formation 

 in the vicinity of Fort Bridger, Wyoming, are those of a number 

 of snakes described by Prof. Marsh. Most of the specimens, he in- 

 forms us, "belonged to constricting serpents, closely related to the 

 modern Boas of South America, although considerably smaller and 

 generically distinct. A few of the specimens indicate snakes of moder- 

 ate size, with apparently quite different affinities." Prof. Marsh re- 

 fers the remains to no less than five species of there extinct and 

 peculiar genera, which he names as follows : 



BoAvus, Marsh. 

 Boavus occidentalis. Boavus agilis. Boavus brevis. 



LiTHOPHis, Marsh. 

 IdtJwpMs SargenU. 



LiMNOPHis, Marsh. 

 Limnophis crassus. 



FISHES. 



^ The Green Eiver shales, in one locality on the line of the railroad, 

 teem with such a profusion of well-preserved fishes that the place has 

 been named the Petrified Fish Cut. The formation and fishes are 

 probably of cotemporaneous age with the iormatiou and its remains of 

 other vertebrates, indicated in the preceding pages. It was one of these 

 fossil fishes, obtained in this locality in 1856 by Dr. John B. Evans, and 



