Prof. A. Mousson on the Molluscan Fauna of the Canaries. 85 



grooving; by the less expanded mouth, with nearly sharp, 

 scarcely thickened peristome, whilst the lower part of the lip in 

 both the other species is very broadly developed and coloured. 

 On the other hand, the aspect of this form, with its very con- 

 stant characters, obvious even in the youngest individuals, of the 

 widely flatter shape, the sharp thread-like keel, and the strongly 

 marked perforation, seem sufficiently to justify its separation 

 from the Canarian pisana, which occurs abundantly on the self- 

 same islands, without, as it appears, transitional states. 



On the contrary, the connexion with H, arietina, Rossm. 

 (Zeitschr. 1846, 17. 2), collected by Dr. Willkomm in the Spanish 

 Sierra de S. Cristoval, which is rare in collections, is less clear 

 to me, and may perhaps rest on similar diflerences to those be- 

 tween our var. geminata and typical pisana, namely the sharper 

 sculpture and the aberrant colouring. Were arietina identical, 

 however, as Herr Pfeiff'er suspects (Monogr. i, 176), with planata 

 of Ch., the affinity with our form would be but slight. 



3. Helix granostriata, MSS. 



Testa umbilicata, lenticularis, solidula, transverse seriatim granulata 

 et sulculata, opaca, griseo-albida, unicolor vel interrupte fusco- 

 bifaseiata ; spira depresso-conica, summo corneo ; anfractus o-b\ 

 superne plani, filo-carinati ; carina subserrulata ; ultimus non de- 

 scendens, infra vix convexiusculus ; umbilicus parvus^ \ diametri 

 non superans ; apertura securiformis ; peristom. rectum, intus 

 labiatum, marginibus non approximatis, columellari non reflexo. 



Diam. maj. 8, minor 6|^, alt. 3-3| millim. 



At the first glance, this pretty species reminds one of H. Se- 

 tubalensis, Pfr., or of the truly scalariform argonautula, Webb 

 (D^Orb. ii. 64) ; but both have the under side more convex, a 

 much wider umbilicus, a much coarser transverse striation, and 

 more prominent keel ; moreover, both are entirely without the 

 elegant rows of granules in the direction of the striae of growth, 

 which indicate a slight approach to the Madeiran polymorpha- 

 group. The two dark interrupted bands on the upper and under 

 sides, disappearing on the spire in horn-coloured spots, recall to 

 mind the colouring of the group of Helix tumulorum, with the 

 members of which, however, no confusion is possible. 



This species is also found on both islands. The example from 

 Fuerta Ventura is somewhat stronger in structure and in sculp- 

 ture than the other from Lanzarote, but partakes of all its other 

 characters. 



4. Helix per similis, Shuttl. (Diagn. n. Moll. 1852, 1. 7). A 

 few examples of this species, found in Lanzarote, are not to be 

 distinguished from those which Herr Blauncr collected in Palma ; 



