312 The MoUuscan FainUy Planorbidae 



PLATE 38 

 Menetus 



1,2,4-10. Menetus opercularis (Gould). From Mountain Lake, San Francisco, Cali- 

 fornia; collected by H. Walton Clark. 



1. Genitalia dissected and organs separated. 



2. Section of prostate near distal end. 



4. Head showing position of pseudobranch. 



5. Section of ovotestis. 



6. Penial gland with cup expanded. 



7. Albumen gland. 



8. Section through penial complex showing natural position of penial gland. 



9. Albumen gland in natural position overlying stomach. 



10. Exterior view of penial complex. 



3,11-15. Menetus cooperi calUughjptus (Vanatta). From Crescent City, California; 

 received from Dr. G. D. Hanna. Also from Quatsino Sound, British Columbia; 

 collected by A. Peake. 



3. Section of prostate about midway of its length. California sjiecimen. 



11. Penial complex from the outside. California specimen. 



12. Penial complex. British Columbia specimen. 



13. Entire prostate. British Columbia specimen. 



14. Cross section of prostate and uterus near front end. British Columbia specimen. 



15. End of verge showing central outlet of sperm canal. British Columbia specimen. 



Line near figure indicates 1 mm. in length. Line at left of fig. 10 is also for 

 figs. 7 and 8. Line at left of fig. 14 is also for figs. 2, 3, 5, 6, 14, and 15. 



