90 



is relatively aljuut as lung as in the P^nglisli Flesiosauri. and the adjacent part 

 of the bone has a similar form. 



MeasuremenU. 



M. 



Lcii^lli of tljc iiiiturior ceivicul 0. 06'.i 



Depth <it' tlie articular face of the anterior cervical ' . . 0. 050 



Width of the articular face of the anterior cervical 0.050 



Length of the posterior cervical 0.070 



Depth of the articular face of the po^sterior cervical 0.052 



Width of the articular fare of the posterior cervical 0.090 



Distance between parapophvsial pits 0.048 



I.tngth of the anterior dorsal vertebra 0. OiiO 



Depth of the articular face of the anterior dorsal 0.06a 



Width of the articular face of the anterior dorsal 0. 072 



Width of the neural canal on the centrum ii. 017 



Long dianieti'r of the proxinial end of the clavicle o. 114 



This saurian is readily distinguished from the Elasinomurus plati/urus, 

 Cope, by the relatively shorter cervical vertebra? and the regular acute ridges 

 on the exterior surfaces near the margin of the articular faces, as well as the 

 less contracted form ul' all tlie vertebral centra. As the neural arches and 

 the cervical parapophyses are not coossified witii the centra, the species is 

 referred to the genus Plesiosaurus. 



The bones of this reptile and those of a smaller species, probaldy a 

 CUdastes, were found in close proximity, near Sheridan, Kansas, by Joseph 

 Savage, of Leavenworth. According to this gentleman, the vertebral column 

 of the CUif/ftden was found immediately below that of the plesiosauroid, and 

 ill a reversed position, as though it Iiad been swallowed by the latter, and larger 

 reptile. The largest vertelM-ag of the CTtddsfe.s were about three-quarters the 

 length and oiic-fourtli (he diameter of those oi' the plesiosauroid, and the 

 animal must liave furnished a large, or at least a long, mouthful for its captor. 

 The bones of the GUdmtes were not in good condition, and resembled those 

 of C. rineildiuiii. Cope, (hough smaller. 



TESTUDIXATA. 



Thisoidci is l)ii( sparingly represented in the marine tormation of No. 3, 

 and more abundantly in the fresh-water beds of No. (J. ()i the former, there 

 are three species, two of them with natatory limbs of the character now 

 known among sea-turtles. Of the latter, all are Triontjchidce and Emiididm; 

 the land-tortoises not iippeariiio- amonsr them, ticcording to pre.sent information. 



