SAINT HELENA. 543 



Bulimus exulatus, Pfeiff., Mon. Hel. iii. 301 (1853) 

 Achatina exulata, Melliss, St. Hel. 123 (1875) 



Habitat ' in St. Helena ' (Lefroy) ; an omnino semifossilis ? 



There is nothing in the published diagnoses of this species 

 to imply that it was discovered in a subfossilized condition, nor 

 can I perceive any note as to the exact spot where it was met 

 with ; therefore I do not know on what authority Mr. Melliss 

 cites it as having been obtained in the cutting of the Sidepath- 

 road above the Briars. My own belief however is that in all 

 probability it was as much subfossilized as are the bleached and 

 still coloured examples of the B. helena, Quoy, which lie scat- 

 tered loosely in many places on the summit of the Barn ; and 

 until further evidence therefore has been adduced, I suspect 

 that it will be safer to treat it as belonging to the extinct fauna 

 of the island, though with the appearance of its having lingered- 

 on (like the B. helena) into comparatively recent times. 



Judging from Pfeiffer's description (which appears to have 

 been drawn out from a specimen in the collection of the late 

 Mr. Benson, and which was found by Mr. Lefroy), as well as 

 from the excellent figure which is given in Eeeve's ' Conch. 

 Icon.,' the present Bulimus, which can hardly therefore be 

 wholly subfossilized, would seem to be diaphanous and of a 

 griseous white, but nevertheless dappled with a few still whiter 

 and more opake spot-like markings; and it is also of a gra- 

 dually yellower tinge towards the apex of the spire. It is 

 rather smaller and narrower than any of the following species 

 (its greatest length being scarcely 9 lines, and its greatest 

 breadth about 3^), and its surface is said to be somewhat roughly 

 and closely crowded with the fine thread-like costae of growth. 



( Mesiotus, Pfeiff.) 



Bulimus helena. 



T. tenuis, ovato-conica, profunde perforata, dense et irregu- 

 lariter costulato-striata striisque paucioribus spiralibus decus- 

 sata, lutescenti-fusca (nisi, saepius, decolorato-decorticata) ; an- 

 fractibus 6 convexiusculis, sutura valde profunde et subito im- 

 pressa ; columella subcontorta ; apertura ovali ; peristomate 

 acuto, marginibus callo junctis, dextro superne (i. e. ad inser- 

 tionem) subangulatim sinuoso, columellari late reflexo et albo. 

 Di'im. maj. 5^ ; long. 9^ lin. 



Helix helena, Quoy et Gaim., Astrol. ii. 111. t. 9. f. 8, 9 



(1833) 



Bulimus helena, Lam. (ed. Desk.), 52. 245 (1836) 

 Pfeiff., Mon. Hel. ii. 198 (1848) 



