330 TEST ACE A ATLANTIC A. 



more open, but which shapes-out at its commencement a peculiar 

 and very distinct circular keel on the under-part of the basal 

 volution. It is also, on the whole, a little darker, or browner, 

 than the rotundata ; and it is less sculptured beneath (at any 

 rate outside the above-mentioned circular keel) with costate 

 lines. 



This would appear to be one of the most local of the Ca- 

 narian Land-shells, and indeed one of the rarest, the only 

 district in which I am aware that it has hitherto been found 

 being around Garachico, in the north of Teneriffe. It was met 

 with there, in 1861, not uncommonly, by Mr. Lowe, having 

 previously been taken, in the same locality, by Blauner. 



Patula retexta. 



Helix retexta, Shuttl., Bern. Mitth. 139 (1852) 

 Pfei/., Man. Hel iii. 115 (1853) 

 Patula retexta, Mouss., Faun. Mai. des Can. 24. pi. 2. 



f. 5-8(1872) 

 Helix retexta, Pfei/., vii. 212 (1876) 



Habitat Palmam ; a cl. Blauner sub foliis dejectis lecta. 



This species and the following one are the only Canarian 

 Patulas which I have not myself had an opportunity of ex- 

 amining. Comparing it with the Teneriffan P. engonata, and 

 the P. Guerineana, Lowe, from Madeira, Mousson says (I. c. 

 24) : ' Elle ne presente ni la carene, ni Tangle au pourtour de 

 rombilic de la P. engonata ; le dernier tour est plus lisse ; la 

 suture marginee d'une fine ligne blanche. L'espece la plus 

 proche est la P. semiplicata, Pfr. (Guerineana, Lowe) de Ma- 

 dere, mais celle-ci n'a pas de suture marginee, un ombilic encore 

 plus large, des tours plus etroits quoiqu'en nombre egal, et une 

 costulation plus grossiere.' 



The P. retexta was taken by Blauner in Palma, where how- 

 ever it was not met with by either Mr. Lowe or myself. 



Patula scutula. 



Helix scutula, Shuttl., Bern. Mitth. 139 (1852) 

 Pfei/., Mon. Hel. iii. 108 (1853) 

 Patula scutula, Mouse., Faun. Mai. des Can. 24 (1872) 

 Helix scutula, Pfei/., Mon. Hel. vii. 186 (1876) 



Habitat TenerifFam ; sub ligno emortuo a cl. Blauner bis 

 detecta. 



As already stated, this is one of the few Canarian species 

 which I have not been able to inspect. It appears to have been 

 unknown also to Mousson, who remarks (1. c. 24) : ' Cette 

 espece m'est inconnue. Par sa forme tres deprimee, le nombre 



