782 PROF. G. C. BOURNE OX THE 



suppovtiug cells being liei-e distinctly ciliated and the deeply 

 staining mucinogenous cells conspicuous. This epithelium is 

 thrown into a distinct spiral ridge, which winds round the uppier 

 part of the V-shaped duct nearly as far as the entrance of the 

 duct of the receptaculum seminis. Here the epithelium changes 

 its character ; the deeply staining mucinogenous cells disappear 

 and gi\-e place to vevj numerous long tubular gland-cells with large 

 oval basal nuclei, the tube-shap>ed cell- body coarsely alveolar and 

 the alveoli containing lai'ge refringent non-staining spherules. 

 Wedged between these are the ciliated cells, with elongated nuclei 

 at about the middle of their length, very attenuated basal ends, 

 and somewhat expanded wedge-shaped distal ends, each with a 

 distinct striated border and a tuft of fairly long cilia. The i-ecep- 

 taculum seminis (PI. XXXTIT. fig. 37) is lined by a low columnar 

 ciliated epithelium of uniform character. The cell-bodies are finely 

 gi'anular and stain readily ; the nuclei spherical and deeply 

 staining. Each cell has a distinct striated border and bears a tuft 

 of long coarse cilia. The spermatozoa in the receptaculum are all 

 arranged with their heads directed towards the centre, their tails 

 outwards and entangled among the cilia of the epithelium. The 

 receptaculum and its duct are invested by a very stout coat of 

 muscular fibres. 



The ti-ansition from the upper end of the ascending limb of the 

 V-shaped duct to the narrow tube of the oviduct is abrupt. The 

 oviduct is lined throughout by an epithelium consisting of long 

 columnar cells bearing specially long and coarse cilia. Tlie cha- 

 racters of these cells are shown in fig. 38 (PI. XXXYII.). 



The cfecum of the ootype is lined by an epithelium difiering 

 from that of the rest of the ootype in the absence of glandular cells. 

 The walls of the cjecum, like those of the hinder moiety of the 

 ootype itself, are provided with a tolerably thick coat of muscular 

 fibres, mostly disposed circularly. The muscular coat is not folded, 

 but the epithelium is disposed in longitudinal ridges due, as seen 

 in fig. 39 (PI. XXXVII.), to the greater length of the cells com- 

 posing them : this figure is from Orohophana ponsonhyi and not 

 from Alcadia ; in the latter genus the cells ai'e somewhat longer 

 and more slender, but otherwise similar in character. As is shown 

 in the figure, the cells are club-shaped with rounded ends projecting 

 into the lumen of the ciecuni ; they do not bear cilia. It is the 

 presence of this characteristic epithelium in the bilobed sac full 

 of spermatozoa leading into the hinder end of the ootype in Palceo- 

 helicina and Orohophana which leads me to identify the sac in 

 question with the caecum of the ootype of Alcadia and Eutrochatella 

 rather than with the receptaculum seminis, and it is further to be 

 remarked that in the non-ciliated bilobed sac the spermatozoa are 

 arranged pell-mell, with their heads and tails in all directions 

 instead of being definitely oriented as they are in the ciliated 

 receptaculum seminis. 



The distal third of the vagina is lined by an epithelium consisting 

 for the most part of highly vacuolated clear cells with basal nuclei, 



