310 The Molluscan Family Planorbidae 



PLATE 37 



Planorhula armigera (Say) 



From Murphy Creek swamp, near Madison, Wisconsin; 

 collected by J. E. Morrison. 



1. Section of prostate near middle of gland. 



2. Section of prostate near middle. 



3. Portion of genitalia showing relationship of o\iduct, sperm duct, ovisperm duct, 



and carrefour. 



4. Genitalia dissected and organs separated, with albumen gland in natural position. 



5. Head and foot showing pseudobranch and pneumostome. 



6. Section of penial gland. 



7. Section of ovotestis to show paired condition of diverticula, which are e.xtended 



laterally, appearing as though digitate. 



8. End of verge to show outlet of sperm canal. 



9. Penial complex showing muscles and general form of vergic sac and preputium. 



10. Penial complex of small, immature specimen showing wide form of preputium. 



11. Section of penial complex showing penial gland spread out and opened, with a 



short, internal duct. 



12. Verge in vergic sac. 



Line near figure indicates 1 mm. in length. Long line at left of plate is for 

 figs. 6, 7, and 8. Long line at right of plate is for figs. 1 and 2. 



