400 TESTACEA ATLAXTICA. 



which are elevated in the centre of each whorl into an obscure 

 in ftl'tal unequally crenulated keel, and into a rather more 

 pronounced one in the usual place, — i.e. along the dorsal line 

 of the basal volution. 



The H. mvrcmdoe (the specific title of which was selected in 

 commemoration of Mr. Gray's yacht ' the Miranda,' in which 

 we visited the several islands of the Canarian archipelago) was 

 taken abundantly by Mr. Lowe and myself in Gomera, — namely 

 on the dry and rocky slopes above and around San Sebastian, 

 particularly those on the northern side of the ravine ; and we 

 subsequently met with a few examples of it in Hierro, — on the 

 ascent from the landing-place to Valverde. 



The H. nodosostriata, of Mousson, founded upon a single 

 example, appears to be merely a larger and rather more de- 

 pressed form of the H. miranda?, in which the prominences are 

 more developed, and the base somewhat more coarsely and 

 irregularly sculptured. We met with it in company with the 

 typical form, into which it appears gradually to merge. 



(§ Diseuht, Lowe.) 



Helix argonautula. 



Helix argonautula, W. et B., Ann. des Sc. Nat. 28. syn. 21 



(1833) 

 „ „ d'Orb., in W. et B. Hist. 64. t. 2. f. 



16-18 [nee f. 13-15] (1839) 

 „ „ Mouss., Faun. Mai des Can. 55 (1872) 



„ „ Pfeiff., Mon. Hel. vii. 212 et 551 



(1876) 



Habitat Canariam Grandem; sub lapidibus ad Arguineguin 

 lecta. 



The present Helix would appear to be one of those which 

 was detected originally by M. Terver, of Lyons, amongst dried 

 orchil ; and although the latter was of doubtful origin, the H. 

 argonautula was nevertheless admitted by Webb, without 

 further enquiry, into the Canarian fauna. However rash such a 

 proceeding may have been (for the same amount of looseness, as 

 regards the evidence for the exact localities, resulted in the 

 introduction into his list of species which are essentially 

 Madeiran, and others which are equally peculiar to the Cape 

 Verdes), it at least in this particular instance had the advantage 

 of placing no geographical error upon record, for the Helix in 

 question happens fortunately to be a Canarian one. Still, 

 nothing; could of course be said about the island in which it was 

 found, for it was only (as it were) by mere accident that even 

 the archipelago itself was correctly guessed at ; and therefore it 



