24 On the Generative System in the Genus Testacella. 
are fertilized in this broad pouch-like portion. The herma- 
phrodite gland is slightly larger than in 7. haliotidea and the 
duct longer. 
Testacella Mauget, Fér. (Pl. I. fig. 3.) 
In this species the vestibule and vagina are rather 
easicr to distinguish than in the preceding one. At the 
junction of the two organs the penis passes off; it commences 
as a narrow tube, and then broadens out into an expanded 
head. It is much longer than in TZ. scutulum. ‘The vas 
deferens previous to entering the prostate is thrown into a 
series of convolutions; these were characteristic of all the 
specimens dissected and quite unlike anything I have pre- 
viously seen in this organ. The receptacular duct commences 
as an ovoid dilatation from the vagina, and is continued as a 
long narrow tube, which enters the receptaculum seminis 
laterally, reminding one somewhat of the condition in Arion 
fasciatus, Nils., only the shape here is oval, and not tapering 
and pointed as in that species. The oviduct and prostate are 
sharply folded upon each other, a character fairly constant. 
The hermaphrodite gland-is somewhat triangular in shape 
and readily distinguishable from that organ in either of the 
two preceding species. 
Variation. 
Although a large number of specimens of each species have 
been dissected, the amount of variation noted in any indi- 
vidual species was very slight and unimportant. 
In 7. haliotidea the flagellum exhibits a series of minor 
variations, being either a straight tapering tube with the distal 
portion sometimes dilated, or it forms a dilatation at an angle 
to the general body, not unlike the head of a golf-stick. I 
have already referred to the variation in the form of the penis 
(Pl. I. fig. 4). 
In 7. scutulum the penal retractor muscle often exhibited a 
division into two portions, while in others there was a small 
retractor muscle given off below the ordinary one. 
Summary. 
There are certain resemblances in the form of the genera- 
tive organs in 7. scutulwm which connect it with 7. Mauget, 
such as :— 
a. The dilatation of the proximal portion of the recep- 
tacular duct. 
