CANARIAN GROUP. 399 



comparatively indistinct. Its umbilicus, too, is relatively a 

 little larger, or more open, and its aperture is not quite so 

 rounded. 'Elle est,' says Mousson, 'plus deprimee que la 

 Despreauxii, souvent presque plate en haut; 1'ombilic plus 

 etroit dans les individus coniques, s'ouvre dans les deprimes 

 jusqu'a i- du diametre ; les asperites sont plus fines et moins 

 dominantes ; dans 1'espace qui longe la suture et dans la partie 

 de la base qui suit la carene, on observe de simples stries 

 costulees, qui continuent sur les tubercles (ce qui n'est pas le 

 cas dans la Despreauxii) ; la carene secondaire est en retrait 

 sur la dorsale et ne sort pas du cone spiral ; souvent elle se 

 reduit a une ligne de petites nodulations, qui quelquefois dis- 

 paraissent entierement,' 1'ouverture est moins ronde, son bord 

 est interrompu sur un certain espace et non entier. En un mot, 

 cette forme, qui habite les deux iles de TEst qui sous tous les 

 rapports se lient intimement, est une Despreauxii, dans laquelle 

 tous les caracteres ont perdu le leur acuite et se sont rapproches 

 des H. mirandce, Lowe, et granostriata, Mousson.' 



Helix mirandse. 



Helix Mirandse, Lowe, Ann. Nat. Hist. vii. 107 (1861) 

 5 , Pfwff; Mon. Hel. v. 214 (1868) 



Mouss., Faun, des Mai. Can. 51. pi. 3. 



f.. 7-9 (1872) 



Habitat Gromeram et Hierro ; in ilia in collibus aridis 

 apricis prope San Sebastian sub lapidibus sat copiose reperta, 

 sed in hac inter portum et Valverde multo rarior. 



This perhaps is rather the smallest member of the Turricula 

 group which has hitherto been detected at the Canaries, the 

 larger examples measuring only about 3J lines across their 

 broadest part ; and it is also the most brightly coloured, its 

 surface being of a dusky white with a more or less interrupted 

 darker band both above and below, and with the spire ad- 

 ditionally mottled with very irregular transverse patches and 

 lines. Although somewhat trochiform in outline, the shell is 

 nevertheless less conical and elevated than that of the H. Des- 

 preauxii, its perforation is relatively larger, and its aperture 

 (which is less angulated externally, and is somewhat darkened 

 within) has the margins of the peristome (which is itself 

 whitish) more distant and interrupted. Its under portion 

 (instead of being roughened with coarse scabrous elongated 

 tubercles and tortuous callosities) is simply striated with fine 

 radiating costate lines ; while the upper region has the latter 

 very oblique and flexuose, but supplemented by short additional 

 obtuse transverse ridges, or elongate tuberculiform prominences. 



