343 



The epiplastrals occupy 44 mm. of the midline; the hyoplastrals, 125 mm.; the hypoplas- 

 trals, 120 mm.; the xiphiplastrals, 8 mm. At the junction of the hyoplastrals and hypoplas- 

 trals, at the midline, the thickness is 17 mm. 



Measured on the midline the gulars are 57 mm. long; the humerals, 40 mm.; the pectorals, 

 73mm.; the ahdominals, 115 mm.; the femorals, 70 mm.; the anals, 52 mm.; both the gulars 

 and the pectorals encroach on the entoplastron. 



In many respects this species resembles E. wyomingensis of the Bridger beds. It is, how- 

 ever, improbable that the latter species continued on into the Uinta epoch. Furthermore, 

 differences are presented, notably in the greater width of most of the vertebral scutes. 



Genus PAL^OTHECA Cope. 



Species small, with thick and solid bones. A dorsal keel present. Scutal sulci deeply 

 imprest. The epiplastral lip projecting and the inguinal buttress probably ascending above the 

 borders ot the fifth and sixth costals. 



Type: Palrfotheca polycypha Cope. 



This hardly definable genus was establish! by Cope to contain his species P. polycypha 

 and P. terrestrts. These he afterwards referred to Emys. As there is neither evidence nor 

 probability that the species belong to Ernys as now understood, the species must be removed 

 to some other genus. It is possible that they belong in Echmatftnys, but of this there is little 

 evidence. They are very imperfectly known species; and as the genus Pala-otheca has been 

 already establish! for them, it seems that no confusion or inconvenience will be produced in 

 retaining them there until more is ascertained regarding their structure and relationships. 



Cope suspected that these small turtles might be the young of species already described 

 from adult remains, but he concluded that they had too many features of maturity to be merely 

 young animals. Cope thought also that they showed relationships with the modern genera 

 Terrapene (Cistudo) and Testudo; but there appears to be little probability of this. 



Unfortunately the types ot both the species here described are extremely fragmentary. 



Palaeotheca polycypha Cope. 



Palteotheca polycypha, COPE, Palaeont. Bull., No. I, 1872, p. 463; Proc. Amer. 1'liilos. Soc., XII, 1873, 



P- 463. 



Emys polycyphus, COPE, Sixth Ann. Report U. S. Geol. Surv. Terrs., 1872 (1873), p. 625, 629. 

 Emys pol\c\pha, COPE, Vert. Tert. Form. West, 1884, pp. 129, 131, plate xviii, figs. 2O-22. 



The type of the present species is in the U. S. National Museum and bears the catalog 

 number 4097. The species was based on very meager materials and only a portion of this was 

 figured. The remains were found in the Bridger beds, but the exact locality and level were not 

 communicated. 



The following is Cope's description: 



This species of tortoise is indicated by vertebral, costal, and marginal bones of very small indi- 

 viduals. These bones are, however, not only thoroughly ossified, but are very stout, indicating the adult 

 age of the animal. The deeply impressed scutal sutures, and heavy proportions, as well as the elevated 

 carina of the carapace, indicate affinity with Cistudo, or, perhaps, Testudo, As a generic character, 

 it may be noted that the vertebral bones are subquadrate, and support the neural canal without 

 intervening lamina. 



The carina of the carapace is abruptly interrupted at intervals; sometimes with, sometimes with- 

 out, a pair of pits, one on each side. The marginal bones are well secured and the scutal sutures are 

 deeply impressed on them. 



Measurements. 



Meter. 



Length of vertebral bone 0.009 



Width of vertebral bone 0085 



Length of marginal bone 01 



This is the least of the tortoises of the Bridger formation. 



The measurements given above of the neural (vertebral bone) apply to neither ot those 

 figured by Cope. The original of his fig. 20 represents a neural 8 mm. long and 8 mm. wide. 



