82 Prof. A. Monsson 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 101 f 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 Teneriffe would seem to 

 possess seven or eight times more species than the not much 



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



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

 ties found by Herr Blaimer in Teneriffe 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 course, 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 Teneriffe 

 and Palma alone, during a three or four 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 spurious species 

 which have been at different times erroneouslv introduced into the list. — Tr, 



