14 THE ROYAL SOCIETY OF CANADA 



Included in the collection of 1913, from the Belly River formation 

 at the type locality, is a complete shell of this species in which the 

 structure and form, in both plastron and carapace, are well preserved, 

 supplying the deficiencies of the material hitherto available. This 

 interesting specimen was discovered by L. Sternberg of the collecting 

 party of last summer, and corresponds almost exactly in size with 

 the type. 



The following general description of the carapace of this species, 

 with more particular reference to its hinder half is now given. 



The carapace is nearly as broad as long, and is broadest in its 

 hinder half. The margin in front is sinuous and rather flatly curved; 

 postero-laterally it is scalloped, and narrowing rather rapidly back- 

 ward, is flattened behind. The upper surface is moderately arched. 



Carapace of Boremys pulchra, Lambe. 

 One-half the natural size. 



S.C.S., supernumerary costal scute; SM.S., supramarginal scute; pn., preneural 

 bone; py., pygal bone; spy., suprapygal bone. 



