1892.] LAND-SHELLS OF ST. HELENA. 



265 



BuLiMUs (Pachyotus). 



14. BuLiMus auris-vxjlpina (Chemnitz). (Plate XXII. 

 figs. 11-11 rf.) 



Eab. All along Sugarloaf Ridge (Turfon). Extinct. 



With regard to this, the largest extinct snail of St. Helena, 

 Mr. WoUaston admits the resemblance " to a certain extent " to 

 certain Brazilian species, at the same time observing "that much the 

 same type of form exists equally in the Solomon Islands and New 

 Zealand." Whilst agreeing with those remarks, I would point out 

 that although in the Pacific shells referred to the apertures are 

 somewhat similar, the general form, especially of the body-whorl, is 

 much more elongate. On the contrary, B. melanostoma and B. 

 bilabiatus from Brazil, cited by Forbes in comparison, exhibit not 

 only like proportions, but also similar oral characters. 



Captain Turton in his notes remarks : " The shape appears to me 

 to vary immensely, and therefore I have sent as many as 30 speci- 

 mens, so as to show all the intermediate forms. The very slender 

 ones are, I suppose, B. darwinianus, but I can scarcely draw any 

 line between them. I noticed that the different varieties of this 

 shell generally (always, I think) came from different parts of the 

 ridge ; and you will observe that the more recent shells which 

 retain their colour do not grow to the same size as the more fossilized 

 ones." 



I fully concur in the opinion arrived at by Captain Turton 

 respecting B. darwinianus (Plate XXII. fig. 11 d) being merely an 

 elongate form of the B. auris-vulpinu. 



His other observation, with regard to the smaller size of the more 

 recent specimens, is also very interesting. This diminution might 

 be accounted for by the vegetation being less luxuriant and other 

 conditions being less favourable to finer growth than in former 

 times, before the partial destruction of the primaeval forests which 

 then clothed the island. 



The freshest examples are of a light reddish colour and generally 

 of a somewhat darker tint towards the apex. The top of the 

 plications at the suture are whitish, and there is more or less of this 

 colour variously distributed over the surface in the form of irregular 

 streaks and blotches. A few subfossil snails' eggs obtained at 

 Sugarloaf Ridge along with this species evidently from their size 

 belong to it. They are roundly ovate, being 6| millim. in length 

 and 6 broad. Some other much smaller eggs were also found by 

 Captain Turton at the same place, but in this instance it would be 

 mere guesswork to suggest to which species they belong. 



(BULIMULUS.) 



15. BuLiMULus BLOFELDi, Forbes. (Plate XXII. fig. 12.) 



Eab. Side Path ; very common {Turton). 



This species is very like the following in form, but has not the 

 same strong spiral sculpture. However in the best preserved 

 example indications of transverse strise and some oblique faint red- 

 dish markings are observable. 



