CAPE-VERDE GROUP. 497 



and which is compared by Morelet to the H. undata, Lowe, of 

 Madeira, was found in a subfossil state, by MM. Bouvier and 

 de Cessac, in the island of Sal [mis-spelt ' Pal ' in the observa- 

 tions which accompany the diagnosis, an error which is 

 unwittingly endorsed, subsequently, by Pfeiffer]. Being im- 

 bedded firmly in <un plateau calcaire de la cote est,' in all 

 probability it belongs to a fauna which has passed away ; never- 

 theless, with my experience of the many subfossilized species in 

 the Madeiran and Canarian Groups which were long supposed to 

 be extinct, but which have gradually assumed a place amongst 

 living organisms, I cannot adopt the conclusion of Morelet 

 that the H. primceva ' sans doute a cesse de vivre dans 1'archi- 

 pel.' That is a point which can only be decided by further, 

 and more careful, enquiry ; for some of the subfossil Helices of 

 Madeira and Porto Santo which have lately been brought to 

 light in a recent condition had escaped, except as fossils, the 

 united researches of many naturalists for nearly fifty years. 



In his remarks on the H. primceva, Morelet says : 6 Cette 

 coquille, par sa forme et par sa sculpture, offre quelque ressem- 

 blance avec YH. undata de Madere. Elle en differe, toutefois, 

 par une costulation plus grossiere, qui n'est point ondulee, et 

 par la direction normale du dernier tour qui se maintient au 

 niveau de la peripherie. La plupart des echantillons sont des 

 moules interieurs qui permettent seulement d'apprecier la pro- 

 fondeur de Pombilic : chez d'autres, mieux conserves, on recon- 

 nait tres-bien la forme de la coquille dont la spire est conique 

 et generalement attenuee au sommet. L'ouverture ne laisse 

 pas d'incertitude : il n'en est pas ainsi du peristome, engage 

 partiellement dans une pate calcaire de la plus grande dureteY 

 [L c. 236, 237] 



( Leptaxis, Lowe.) 



Helix atlantidea. 



Helix atlantidea, Morel., Journ. des Conch, xiii. 237 (1873) 

 Pfeiff., Mon. Hel vii. 482 (1876) 



Habitat Sal, semifossilis ; a DD. Bouvier et de Cessac re- 

 perta. 



Like the H. primceva, this species was detected in a sub- 

 fossil condition in Sal by MM. Bouvier and de Cessac ; and it 

 seems to have been found in the same calcareous formation, on 

 the eastern coast or" that island. It is said to be somewhat 

 related to the (likewise semifossilized, and apparently extinct) 

 H. chrysomela, Pfeiff., of Porto Santo, in the Madeiran Group ; 

 and Morelet, in his observations concerning it which follow the 

 diagnosis, says : ' Elle rappelle, au premier aspect, YH. chryso- 



K K 



