EXPLANATION OP PLATE 7. 



Fig. 1. Cymbospondyltts petrinus Leidy. Photograph of mounted specimen, no. 9950. about 

 Vj G of natural size. Restoration is limited to the distal portion of some of the ribs. Prom the 

 Middle Triassic of West Humboldt Range, Nevada. 



Fig. 2. Delphinosaurus perrini Merriam. Type specimen, no. 9119, a little less than % of 

 natural size. From the Upper Triassic of Shasta County, California. 



Pig. 3. Delpliinosaurus perrini Merriam. Specimen 10998. About Vio of natural size. Prom 

 the Upper Triassie of Shasta County, California. 



[170] 



