CANARIAN GROUP. 347 



versely-sculptured ridges which are so characteristic of that 

 (equally Teneriffan) species ; and it has more appreciable traces, 

 too, of an obsolete keel. 



Helix Bethencourtiana. 



Helix Bethencourtiana, Shuttl., Bern. Mitth. 143(1852) 

 Pfeiff., Mon. Hel. iii. 270 (1853) 



?5 Mouss., Faun. Mai. des Can. 84. 



pi. 5. f. 3,4 (1872) 

 Pfeiff., Mon. Hel. vii. 478 (1876) 



Habitat Teneriffam ; a cl. Blauner inventa. 



I have not seen this species, which was taken by Blauner in 

 Teneriffe ; but it is said to be much allied to the H. plicaria, 

 from which it is mainly distinguished by its smaller size, and 

 by having its costate ridges perfectly simple, or free from trans- 

 verse sculpture. 6 Cette espece,' says Mousson, ' confondue an- 

 terieurement avec VH. plicaria, et subordonnee par M. Lowe 

 (Ann. Nat. Hist. 3. ser. vii. 110) a VH. Adansoni, Webb [i.e. 

 H. Pouchet, Adans ], a ete nettement definie par M. Shuttle- 

 worth, comme je me suis convaincu sur des echantillons de la 

 main de 1'auteur meme. Elle se distingue de la plicaria par 

 sa moindre grandeur, sa tenuite, par 1'accroissement plus prompt 

 des tours, par des plis distants eleves, mais parfaitement lisses, 

 non creneles, par une ouverture plus regulierement ovale 

 en travers, enfin par un peristome beaucoup moins large, en peu 

 colore. L'absence totale de martelage la separe entierement de 

 la modesta, qui a la meme grandeur.' 



Helix plicaria. 



Helix plicaria, Lam., Encyl. Meth. t. 462 f. 3 

 plicatula, Id., Hist. viii. 81 (1822) 

 plicaria, W. et B., Ann. des Sc. Nat. 28. syn. 313 



(1833) 



d'Orb., in W. et B. Hist. 56 (1839) 



Pfeif., Mon. Hel. i. 291 (1848) 



Desk., Per. Hist. i. 112 (1851) 



Mouss., Faun. Mai. des Can. 81 (1872) 



Habitat Teneriffam ; in collibus apricis circa Sta. Cruz 5 vul- 

 garis. Etiam semifossilis parce reperitur. 



The H. plicaria, Lam., is essentially characteristic of Tene- 

 riife, where it is common on most of the dry and rocky hill-sides 

 around, and above, Sta. Cruz, and from whence it has been brought 

 by every collector who during the last fifty years has visited 

 the island. There is no evidence that it is found elsewhere in 



