CANARIAN GROUP. 427 



Bulimus helvolus, Pfeiff., Mon. Hel. iii. 348 (1853) 

 Buliminus helvolus, 3fouss.., Faun. Hal. des Can. 107 



(1872) 

 Bulimus helvolus, Pfeiff., Mon. Hel. viii. 75 (1876) 

 Habitat Teneriffam ; juxta Sta. Cruz lecta, sed rarissime. 

 The single example from which the above diagnosis has been 

 drawn out, and which was received from Teneriffe by the Baron 

 Paiva, appears to me to belong most unmistakeably to the B. 

 helvolus, W. et B. (said by Mousson to have been found by 

 Gondot, Blauner, and Fritsch near Sta. Cruz), — the only point 

 in which it does not perfectly accord with the diagnosis of that 

 shell consisting in the fact that I cannot detect any traces of a 

 faint angle, or keel, along the dorsal line of its ultimate volu- 

 tion. But its other characters are so pronounced, — particularly 

 as regards its glossy, faintly striated, pale ochreo-corneous con- 

 colorous surface, and the presence of a small thickened tubercle 

 at the right-hand insertion of the peristome, ivhich is se'parated 

 fro'in the angle itself (as in the B. badiosus, Bertheloti, and 

 Consecoanus) by a deep cleft or incision, — that I can have no 

 hesitation in referring it to Webb and Berthelot's species, with 

 a type indeed of which in the British Museum it seems per- 

 fectly to agree. In other respects the B. helvolus is elongate 

 and ovato-fusiform, with its basal whorl a good deal lengthened, 

 and its intermediate ones rather unusually increased ; and its 

 aperture, which is somewhat round, has the peristome but very 

 narrowly expanded. 



Judging from the examples before me, I should say that the 

 B. helvolus is perhaps more nearly allied to the (nevertheless 

 somewhat maculated and striped) B. Moquinianus of Grand 

 Canary than to anything else, — forming a passage, in conjunc- 

 tion with that species, from the variatus-ij'^e, to the larger 

 and less conical forms. 



Bulimus palmensis, 

 T. rimato-perforata, ovato-fusiformis (in medio latiuscula), 

 subtenuis, subpellucida, subopaca (rarius nitidiuscula), irregu- 

 lariter striatula lineisque minutissimis spiralibus hinc inde 

 distinctius et dense cincta, ad basin rugoso-granulata, pallide 

 ochraceo-cornea, interdum etiam subflavescens, rarius plagis 

 obscuris paululum pallidioribus obsolete maculata ; spira 

 breviter et acute conica ; anfractibus 7, planiusculis, ultimo 

 elongatulo; apertura magna, elongata, obliqua, peristomate 

 albido et anguste expanso, marginibus subparallelis, distantibus, 

 lamina tenuissima (interdum vix perspicua) simplici junctis, 

 columellari obliquo et vix reflexo. — Lon. lin. circa 6 ; diam. 

 niaj. 2^. 



