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



worth*, and have raised the whole number of Canarian species, 

 including- some from the collections of M. Terver (in the Mar- 

 seilles Museum) and of M. Moquin-Tandon, to lOlf good species 

 and varieties, besides seven doubtful. But that even this num- 

 ber must be of very little value with reference to most of the 

 islands, is proved by the following comparison of the species 

 authentically attributed to each of the larger, — seven species, of 

 universal diffusion, being moreover here omitted. 



Thus the much-frequented island of Teueriffe would seem to 

 possess seven or eight times more species than the not much 



* Berner Mittheiluu^en, Nos. 241, 242 and 260, 261. 



t There is some diflOiculty about this. The forty-two species and varie- 

 ties found by Herr Blauner in TeneriflFe and Palma alone can scarcely but 

 include some proportion of the sixty-six (comprising seven of doubtful 

 origin) previously enumerated by D'Orbigny; and in that case they ought 

 not, of coiu-se, to be simply added on en masse to the latter, as they appear 

 to have been by our author, in order to form his total amount of " 101 

 good species and varieties, besides seven doubtful." A few more than fifty 

 species and varieties, old and new, have recently been found in Teueriffe 

 and Palma alone, dvuing a three or fom- months' residence, by Mr. Wollaston 

 and myself; but our joint researches in all the other five Canarian islands, 

 during' two or three months of the present year ( 1 858), have not added above 

 twenty-five or thirty distinct species to these fifty or sixty, which include, 

 moreover, several altogether new or undescribed. The whole number of 

 genuine Canarian species hitherto recorded can therefore scarcely exceed 

 seventy or eighty, making due abstraction of the many spui-ious species 

 which have been at different times erroneously introduced into the hst. — Tr. 



