PLATE XLI. 



Trochocebas insignb (page 282). 



Side view <lf'the largest and most perfect specimen of this species that the 

 writef has seen, from the quarries at Stonewall, Manitoba. This speci- 

 men, which is a well-preserved cast of the interior of the shell, was pre- 

 sented to the Museum of the Survey by Mr. John Gunn in 1897. 



From a drawing by Mr. T. E. Calderon. 



