ASHFORD : ON THE DARTS OF BRITISH HELICID^. 243 



Seventeen eggs filled the tube from the albumen gland to the 

 outlet. The oviduct was bent into a semicircle by the unequal 

 lateral distension of the two conjoint passages in that part, 

 rendering the distinction between oviduct and sperm-duct very 

 clear ; the usual loose interfoldings of the former were quite 

 effaced, and the two dart-sacs were widely separated by the eggs 

 passing between them (fig. 12). 



The figures are from specimens collected at Christchurch. 



16. Helix hispida L., pi. ix., figs. 13 — 17. Dart-sacs two, 

 each with an accessory lobe like those of H. rufescens 

 and similarly situated but smaller ; clear white, some- 

 times minutely dotted with brown. Darts two, 

 occupying the outer sac of each pair, usually curved 

 and awl-shaped, or more rarely straight ; base relatively 

 large ; annulus absent. Length about 075 mm. 



The eight stiff little mucous glands, four on each side or 

 verticillate, with their opaque interiors and contracted exits are 

 much like those last described, but they are perhaps rather longer 

 compared with the size of the animal and less inclined to be 

 flexuous. 



So closely are H. Jiispida and H. rufescens alike as respects 

 the organs constituting or connected with the reproductive 

 apparatus that it is difficult to point out any distinction, apart 

 from size, between their dart-sacs (cf Dr. Lehmann in Mai. 

 Blatt, 1869). What slight variations occur in one species, such 

 as the shape of the teliferous sac and its relative proportion in 

 size to the adjacent lobe, appear also in the other (fig. 13). 



In both species the darts too run through the same vari- 

 ations — in curvature, breadth of shaft and pose of base — but the 

 perfectly straight, subcylindrical, belemnite form of the upper 

 part occurs less frequently in H. hispida* (figs. 14, 15). 



Twice only have I met with immature darts. These 

 occurred among a considerable number of specimens collected 

 in the month of March near Stockton-on-Tees and favoured by 



* Care must be taken in mounting these little objects or they may be 

 fixed in such a position as to seem straight under the lens and yet be really 

 Curved. 



