388 



PROCEEDINGS OF THE ACADEMY OF 



[1892. 



ble. Before proceeding with the descrij)tions of genera it may be 

 well to describe briefly the organs to be discussed. 



In the accompanying figure, representing the genitalia of Helix 



-sp. 



Caniisnella platyodon Pfr. 



•plaiyodon Pfr., a species of the island of Hainan, the male system 

 is seen branching toward the right, the feinale system towai*d the 

 left. The systems unite below, forming the vestibule or atrium, 

 sometimes called genital cloaca (cl.) ; and they are also united 

 above ; the hermaphrodite gland or ovotestis, giving off both sper- 

 matozoa and immature ova which travel through the much convo- 

 luted hermaphrodite duct or ovisperm duct, to the base of the 

 albumen gland, where the duct separates into oviduct and vas- 

 deferens. 



The penis (p) is in its simplest form a muscular sack receiving 

 the vas-dejerens (v. d.) and the retractor muscle (r. p.) at its sum- 

 mit. There are often developed upon the penis one or more of the 

 following accessory organs: (1) the appendix,'' a glandular or 

 flagellum-like organ inserted at the middle or near the base of the 

 penis sack (see this volume, plate 18, fig. F, at x, x.) ; (2) the 

 penis-papilla {see p. p. of the annexed figure) seen only by splitting 

 the muscular penis wall. This papilla is perforated near its base 

 for the exit of the sperm atophores ; (3) the epiphallus^ (epi.), a, 



^See V. Ihering, Morphol. u. Syst. Helix, i, p. 396. 



^In the epiphallus the spermatozoa are gathered into variously covered masses, or 



spermatophores. 

 nenstrecke.^ 



Simroth calls the corresponding organ in the slugs the " Patro- 



