JOURNAL OF CONCHOLOGY. 239 



THE DARTS OF BRITISH HELICID^. 



By CHARLES ASHFORD. 

 PART VI. 



14. Helix pomatia L., pi. ix., figs, i — 8. Dart-sac stout, 

 subcylindrical or subclavate ; coats thick, white or 

 pearl-white at all ages. Dart curved, furnished with 

 four equisalient blades having blunt, thickened, smooth 

 margins which end abruptly or even acutely angulated 

 below ; base moderately expanded ; annulus of about 

 1 6 rods. Length 8 to g}4 nim. 



The dart-sac of this species (fig. i) has a general resem- 

 blance to that of H. aspersa in colour, form, and structure, but is 

 usually less oval in shape and often truncately rounded at the 

 free end. The lower part is, for a short distance, fused to the 

 vagina. Its outer coat is remarkably thick and muscular, well 

 suited to the requirements of the formidable weapon it contains. 



On an average, not less than forty little azure-white branches, 

 supported on a short thick pedicle, make up each of the two 

 mucous glands. For their beauty and curious ramification to be 

 thoroughly appreciated they should be isolated and spread out in 

 a little clear water. While resembling in style of subdivision 

 those of our common garden snail they exceed them two-fold in 

 length as well as in number of branches. In the last respect they 

 are extremely variable. I have counted as many as 73 terminals 

 in one gland, and as few as 15 in another adult individual. 

 There exists in H. pomaiia a peculiar tendency for these 

 branches to assume aberrant forms. Figs. 3, 4, 5, and 6 re- 

 present curious malformations met with in about 30 shells 

 collected near Reigate and sent me by Mr. J. E. Daniel, of 

 Epsom. They remind one of the "freaks" in fern-life. 



The dart (fig. 2) is strong, smooth and glossy, always curved 

 and quite devoid of mucous films between the blades. It differs 

 from the dart of H. hortensts, with which, in style of build, it 

 appears at first glance to have much in common, in being fully 

 twice as long, in having the blade-margins roundly thickened 



