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V. CAPE-VEKDE GROUP. 



OUR knowledge of the Land-Shells of the Cape- Verde archi- 

 pelago can scarcely be regarded, hitherto, as more than frag- 

 mentary. The extremely depauperated condition of the islands 

 which have been reduced, through the complete destruction of 

 their aboriginal timber, to a state of dryness and sterility far 

 beyond what we observe in the more northern clusters added 

 to the comparatively short visits which have been paid to them 

 by the different naturalists who have attempted, from time to 

 time, to investigate their natural history productions, has 

 precluded any thorough acquaintance, as yet, with even the few 

 types of life which still remain to represent their primeval 

 fauna. Considering the large number of the islands, the great 

 extent of their combined superficial area, and the considerable 

 elevation which many of them attain (Fogo, the loftiest of all, 

 rising to an altitude of 9,760 feet above the sea), there can be 

 little doubt that a corresponding Molluscous population must 

 once have nourished ; but the wholesale annihilation, by the 

 improvident inhabitants, of their native trees has so far 

 destroyed the central source of humidity that what only a few 

 centuries ago must have been densely wooded ravines and well- 

 filled mountain torrents are now scarcely more than a chaos of 

 black basaltic rocks, abutting on dry cindery slopes and har- 

 dened volcanic mud. Yet even under circumstances so adverse 

 as these some slight traces of the aboriginal Gastropods have 

 been brought to light, about 41 species being the result, so 

 far as I am able to judge, of the united exertions of the very 

 limited number of explorers who have had the opportunity of 

 examining one part or another of this remote and widely 

 scattered Group. 



Although stray notices of a few of the Cape-Verde Land- 

 Shells appeared, from time to time, in earlier publications 

 (including those of Ferussac in 1827, of King in 1831, of Beck 

 in 1838, of Pfeiffer and Shuttleworth in 1852, of Albers in 

 1854 and of Benson in 1856), it was not until 1865 that the 

 catalogue of Eeibisch cited 11 species as a first instalment 

 towards a Gastropodous fauna of the archipelago. Nothing 



