NATURAL SCIENCES OF PHILADELPHIA. 39 



Zonites laevigatus, Pfr., pi. III., fig i. 



I have examined numerous specimens, but have some hesitation 

 in giving my figure and description as absolutely perfect. I had 

 great difficulty in dissecting the species. 



The ovary is short and vagina long. The genital bladder with 

 its duct forms a short cylindrical sac-like organ, opening near the 

 base of the vagina, and tapering at the apex. The penis sac is 

 long, cylindrical, larger at its apex where it receives the vas de- 

 ferens. At its base the penis sac has its opening into the vagina 

 with a short stout organ (fig. 13) with rounded apex, where a re- 

 tractor muscle seems to be attached. This organ may be a dart 

 sac or some form of prostate gland. 



HempMUia glandulosa, BI. and Binn., pi. III., fig. v. vi. 



The testicle is composed of a large globular mass of aciniform 

 caeca. It lies loosely upon, not imbedded in, the upper lobes of 

 the liver. The ovary and oviduct are as usual. The genital 

 bladder is globular, very large, on a short stout duct, entering the 

 vagina near its base. The penis sac is long, cylindrical, larger 

 towards its apex, where both the retractor muscle and vas de- 

 ferens enter. 



In several specimens examined, the penis sac appeared some- 

 what different. It had a large globular bulb (5a) at its apex. 

 The vas deferens (7) entered be3'ond the middle of the length of 

 the sac (5) ; it was greatly swollen (5b) before entering the sac, 

 for a distance equalling about one-half of the length of the sac. 

 At the commencement of this swelling the retractor muscle (6) 

 was inserted. This form of penis sac is figured in fig. vi. 



Tlie balance of the anatomy of Hemphillia seems to be as in 

 the other slugs. 



Helix Kelletti, Forbes (Arionta), pi. III., fig. iv. The Catalina Island form. 



The ovary is light yellow. The oviduct is white. The genital 

 bladder is light yellow. The prostate is large and yellow. 



The whole genital system is long and narrow. The genital 

 bladder is small, globular, on an extremely long and delicate duct 

 which enters the vagina at its upper end. The duct just below 

 the bladder receiA^es a branch duct, ver^^ long, flagellate, three 

 times the diameter of the duct itself. The penis sac is long, stout 

 cylindrical, tapering towards its apex and prolonged into a very 

 long delicate flagellum. The vas deferens enters at the point 



