Farnie. — Tht Structure of Amphibola crenata Marfi/n. 83 



Opening into the common duct are two diverticula, the albumen-gland 

 and the prostate. The albumen-gland {ag) opens into the distal end of 

 the glandular region opposite the point at which it passes into the non- 

 glandular. It is a brownish or orange-coloured tubule, which is very much 

 convoluted, as Hutton described, and forms a spherical mass, around which 

 are wound the numerous coils of the intestine. It is soft and of a somewhat 

 slimy consistency, and its cells secrete a great quantity of mucilaginous 

 material. 



At the commencement of the penis is .situated the prostate (pr). It is 

 a much-convoluted blindly-ending tube, the distal half pure-white in colour, 

 the proximal half bright-yellow. From this end a slender duct leads away, 

 which, after running in the substances of the muscular wall of the penis, 

 communicates with its cavity near its opening to the exterior. 



From the above description it will be seen that the condition of the 

 genital duct in Amphibola agrees with the most primitive condition in the 

 Euthyneura — that is, the duct is a sperm-oviduct throughout its length. 

 To this type of duct Lang (1900) and Pelseneer (1906) give the name 

 " monaulic." 



As far as I can ascertain, the only other primitive pulmonate closely 

 related to Amphibola which exhibits a monaulic type of duct is Siphonaria. 

 Cottrell (1911) shows that the reproductive organs of this genus differ from 

 those of Amphibola in three chief features : There is no separate albumen- 

 gland, but the common duct is itself glandular, and the much-folded walls 

 of this duct constitute the albumen-gland ; the common duct enters the 

 penis close to its external pore and not at its distal extremity ; and there 

 is a large spermatheca, the long duct of which opens into the penis close to 

 the common duct. The absence in Amphibola of a distinct and definite 

 spermatheca seems a peculiarity. 



Limnaea, which has affinities with Amphibola, has a " diaulic " type 

 of genital duct which cannot be compared with that of Amphibola. In 

 Chilina, another primitive pulmonate, the reproductive system of which 

 Lang (1900) figures and describes, the genital duct is " diaulic," the open- 

 ings of the sperm-duct and oviduct being at some distance from each other. 

 Considering the close relationship of Amphibola and Chilina, one would 

 have expected a greater similarity in their reproductive systems. 



Quoy and Gaimard (1832) described the reproductive system of 

 Amphibola. They called the hermaphrodite gland the " ovary," and the 

 hermaphrodite duct the " oviduct." The albumen-gland they named 

 " testicule," and the genital duct which runs up on the right side the 

 " uterus." The opening of the female portion of the duct they figure on 

 the right side of the body, to the left of the anus. The penis they describe 

 as opening near the eye. in the place where the right tentacle would be if it 

 were represented in the figure. 



Hutton (1879) correctly describes the hermaphrodite gland and the 

 hermaphrodite duct. The albumen-gland he says consists of two parts — 

 an albumen-gland proper and an accessory gland. The albumen-gland 

 proper opens into the hermaphrodite duct by a duct. According to him, 

 the hermaphrodite duct appeared to divide beyond the albumen-gland 

 into a large sacculated " oviduct," and a narrower but still broad " vas 

 deferens" (which is the "common duct" of my account), but , he could 

 not satisfy himself as to how the oviduct left the hermaphrodite duct. He 

 describes it as running along the left of the rectum, to which it is firmly 

 attached. " It appears to open inside the respiratory cavity," but of this he 



