140 University of Michigan 



PLATE XII 



The hair-line indicates a length of one centimeter; the dimensions of 

 the shells figured are given in the text. 



Fig. a. Tudora aurantia aurantia. Male and female, from B2. 



Fig. B. Tudora aurantia wassauensis. Male and 2 females, from 

 B8; the right-hand figure is the type. 



Fig. C. Tudora muskusi muskusi. Male and 3 females, from C17b; 

 the second figure from the left is the type. 



Fig. D. Tudora rupis newportensis. Male (type) and 2 females, 

 from CI. 



Fig. E. Tudora rupis rupis. Male and female (type), from C2a. 



Fig. F. Tudora muskusi grandiensis. Two males and two females, 

 from C14; the right-hand figure is the type. 



Fig. G. Tudora muskusi iullenensis. Male and female (type), 

 from C13. 



Fig. H. Tudora muskusi X Tudora fossor djerimensis. This speci- 

 men appears to be a hybrid between these two species. The operculum 

 is also somewhat intermediate, but is much closer to muskusi. From C17b. 



Fig. I. Tudora fossor djerimensis. Male and female (type), 

 from C17b. 



