94 University of Michigan 
PIES, WILL 
All drawings are made with the aid of the camera lucida. The scale 
of figures I, 2, 4, and 6 is given under figure 4, while that of figures 
12, 13, and 14 is under figure 12. Each of the other figures has its 
own scale. The laterals and marginals are numbered as a continuous 
series, from the center out. 
Figure 1. Guppya gundiachi; radula. 
Figure 2. Guppya sterku,; radula. 
Figure 3. Guppya gundlachi; jaw. 
Figure 4. Guppya trochulina; radula. 
Figure 5. Guppya trochulina; jaw. 
Figure 6. Euconulus elegantulus; radula. 
Figure 7. Averellia coactiliata; radula. 
Figure 8. <Averellia sumichrasti; radula. 
Figure 9. <Averellia coactiliata; jaw. 
Figure 10. Averellia sumtchrasti; jaw. 
Figure 11. Thysanophora pilsbryi; detail of sculpture. 
Figure 12. Thysanophora pilsbryi; top view. 
Figure 13. TJ. pilsbryt; front view. 
Figure 14. 7. pilsbryi; under side. 
