WATSON : DEFICIENCIES IN THE VERTIGININ^. 271 



anterior end, the swollen part functioning as a vesicula seminalis. 

 There is a large albumen gland, as in all the specimens described in 

 this paper. The prostate gland is small, consisting of a very few, 

 short tubules, situated at the inner side of the hinder end of the 

 spermoviduct where it joins the albumen gland. The broad 

 glandular genital duct, which passes forwards from the albumen 

 gland, is divisible into a posterior and an anterior portion, which 

 differ in their histological structure. The posterior part is the larger, 

 and may be termed the spermoviduct ; the anterior part may be 

 called the glandular oviduct, and is specially characterized in this 

 species by the fact that its gland-cells contain a granular secretion 

 which stains blue with haematoxylin. The last division passes for- 

 wards into the non-glandular free oviduct, which unites with the 

 narrow receptacular duct, and is continued to the genital opening as 

 a long vagina of simple structure. The receptaculum seminis, or 

 spermatheca, is situated close to the hinder end of the spermoviduct 

 towards its outer side, not far from the base of the albumen gland ; 

 the receptacular duct is therefore very long. 



One specimen collected by Dr. Boycott at Cothill, Berkshire, in 

 November, 1921, and nine additional specimens found in the same 

 locality in June, 1923.^'^ — Five of the latter specimens are without male 

 organs, and closely resemble the examples from Braunton in the 

 structure of their genital ducts. In the remaining individuals from 

 Cothill rather complex male organs are present. The penis is very 

 long, and is somewhat swollen at its hinder extremity ; its walls 

 contain a considerable amount of glandular tissue. Into the posterior 

 end of the penis there opens a long epiphallus, which, however, is 

 much narrower than the penis itself and does not contain gland- 

 cells. The slender vas deferens is very long, running forwards near the 

 oviduct and vagina almost to the genital atrium, and then bending 

 round and passing far back to merge into the hinder end of the 

 epiphallus. The narrow penial retractor is inserted at the junction 

 of the epiphallus and vas deferens. The genital atrium is rather 

 short, and the hermaphrodite and female organs agree closely with 

 those of the specimens without male organs. 



Vertigo antivertigo (Drap.). 

 Two specimens collected by Dr. Boycott at Braunton, North 

 Devon, in August, 1919.— Male organs are present in both individuals. 

 The vas deferens is very long, running forwards beside the oviduct 

 and vagina, and then bending round and passing back a considerable 

 distance beyond the hinder end of the penis. It then bends round 

 again and passes forwards to enter the penis at its extremity, this 

 last part of the vas deferens being slightly broader than the rest, 

 and forming an incipient epiphallus. The penis itself is long, and ia 



^ Only three of these nine specimens were cut into sections ; the rest I 

 dissected in the ordinary manner. 



