96 PROCEEDINGS OF THE MALACOLOGICAL SOCIETY. 



Reproductive Organs. — Hermaphrodite gland consisting of 

 a large number of very small follicles embedded in the posterior 

 division of the liver. Hermaphrodite duct convoluted and some- 

 what swollen during the greater part of its course, bearing a 

 sub-cylindrical vesicula seminalis at its anterior end. Albumen 

 gland very large. Common duct contorted, and divided, as 

 usual, into an opaque prostatic portion, and a more voluminous, 

 translucent, female portion or uterus. Free oviduct long, the 

 posterior part sacculated. Receptaculum seminis or spermatheca 

 large, elongate, with very thin walls. Receptacular duct with 

 thicker walls, unbranched, and short, being about half the length 

 of the free oviduct. Vagina also short, and without any 

 appendages. 



Vas deferens somewhat broader than usual, with a sacculated 

 or closely convoluted appearance as it passes forwards beside the 

 free oviduct. As it bends round towards the penis it is narrower, 

 but it then enlarges again rather abruptly to form a well-marked 

 epiphallus, the walls of which are full of small, opaque white, 

 calcareous glands. The upper end of the epiphallus winds half 

 round the top of the penis before entering it. No flagella or other 

 outgrowths of the male ducts are present. 



The calcareous material within the epiphallus consists of 

 innumerable microscopic granules, varying in length from '002 

 to "006 mm., and usually slightly less than half as broad as they are 

 long. They are, as a rule, of a rather narrow oval form, but some 

 are more irregular in shape, often having the appearance of being 

 double ; while here and there they are aggregated to form small 

 concretions which may exceed "015 mm. in diameter. 



Penis rather large, being about 5 mm. long and swollen towards 

 the middle. The posterior end has the form of a knob separated 

 from the remainder by a slight constriction, and into this knob 

 the epiphallus enters and the short penial retractor is inserted. 

 Longitudinal rows of minute papillae line its walls internally, 

 and it contains a small penis-papilla. The walls of the remainder 

 of the penis have a quite different structure, possessing internal 

 longitudinal folds, two of which are larger and more regular than 

 the others. 



Genital atrium very short, and bearing, in addition to the 

 penis and vagina, an amatorial organ, about 3"5 mm. in length, 

 and having an internal structure rather like that of a sponge. 



No sjDermatophore was found. 



Spermatozoa having both the head and the proximal part of 

 the tail spirally twisted. Head rather narrow, sharply pointed 

 in front, smooth, and larger than usual, being '009 mm. in length. 

 Tail slender, more than '25 mm. long, its proximal part being 

 furnished with a very narrow spiral flange. 



