282 The Molluscan Faintly Planorbidae 



PLATE 23 



Helisoma anceps (Menke) 



1-4,7-11. Helisoma anceps (Menke). From Gillespies Pond, Collinsville, Connecticut; 

 collected bj^ F. C. Baker and Leslie Brewer. 



1. Cross section of penial gland showing cup, folds, and duct. 



2. Section of penial complex to show position of gland in preputium. 



3. Exterior view of penial complex showing short duct on outside of preputium. 



4. Region of the neck showing pseudobranch, pneumostome, and rectum. 



7. Albumen gland from below. 



8. Penial complex of specimen in which gland in preputium has been pushed 



upward. 



9. Cross section of prostate showing multiple form of diverticula. 



10. Cross section of ovotestis. 



11. Genitalia dissected and organs separated. 



5,6. Helisoma anceps latchfordi (Pilsbry). From Meach Lake, Quebec, Canada; col- 

 lected by A. LaRocque. 



5. Diaphragm in preputial sac view from below. 



6. Section through diaphragm showing entrance of gland duct into vergic sac 



cavity just above diaphragm. 



Line near figure indicates 1 mm. in length 



