268 The Molluscan Family Planorhidae 



PLATE 16 



Gyraulus deflectus obliquus (DeKay) 

 From Taylor Lake, Masham, Quebec, Canada; collected by A. LaRocque. 



L Penial complex in vertical section. 



2. Penial complex of specimen with bulbous termination of vergic sac. 



3. External view of penial complex showing relationship of parts. Also male opening 



behind tentacle. 



4. Genitalia dissected and organs separated. 



5. Section through portion of penial complex at junction of vergic sac and preputial 



sac to show thickened portion with papilla. 



6. Stylet. Distal end of verge shows sperm canal outlet at side. 



7. Terminal diverticula of ovotestis, showing de\-eloping ova. 



8. Terminal diverticula of ovotestis from left side. 



9. Section through diverticula of ovotestis. 



10. Distal end of genitalia showing position of sperm duct, oviduct, albumen duct, etc. 



11. Section of prostate near middle. 



12. Section of prostate six diverticula from front end. 



13. Body and foot of animal showing pseudobranch, etc. 



14. Pseudobranch showing network of blood vessels. 



15. Another form of pseudobranch. 



Line near figure indicates 1 mm. in length. Line at middle left of i)late 

 indicates size of figs. 5, 6. 7, 8, 9, 11, and 12. 



