G. R. Wieland — On Marine Turtles. 



329 



It is also of much interest that while in forms like Osteopy- 

 gis a nether nuchal process is wholly absent, there is in the 

 present turtle a mere, although distinct beginning of such a 



2 



Figure 2. — Plastral view of Toxochelys Bauri Wieland, x % nearly. 

 (Drawn from type). — en, Entoplastron ; h, Hyoplastron; hp, Hypoplastron ; 

 x, Xiphiplastron ; /, /, /, the median and the lateral hyo-hypoplastral, and 

 the hypo-xiphiplastral foramina ; 4-7, the plastron-supporting marginalia. 

 Other letters as in figure 1. 



process, and in Toxochelys latiremis a much larger projection 

 for actual cervical articulation. This process thus appears to 

 have arisen in different groups rather than to have been com- 



