274 



of London,' in 1834, twenty new species, among whicli some remained 

 doubtful ; and lastly Mr. Hinds, in 1843, in the work we have pre- 

 viously cited, after having described fifty new species, coming almost 

 all from the Cumingian Collection, gave a prodromus of a complete 

 monograph of the genus, and raised the number of the species known 

 to one hundred and eight. This Monograph, accompanied by very 

 good figures, was published by the author the following year in the 

 ' Thesaurus Conchyliorum ' of Mr. Sowerby. This very considerable 

 number was still farther augmented by Messrs. Adams and Reeve, 

 who described ten species. 



Since the publication of these two works, Mr. Cuming has con- 

 tinually added to his collection all the new species he could obtain 

 possession of. We remark amongst his recent acquisitions some 

 objects most worthy of attention, on account of their elegant orna- 

 mentation and colours, as also the novelty of their forms. To these 

 precious materials put at our disposal, we have joined those we had 

 collected ourselves, and M. Edouard Verreaux has permitted us to 

 add some other species in order to render our task more complete. 



Thanks to so favourable a combination, we are able now to add 

 seventy-five species to those already known, which has raised the 

 number to nearly two hundred, if we exclude duplicates and doubt- 

 ful species ; for, had we enumerated indiscriminately all the names 

 given, they would have amounted to more than two hundred. 



We are happy to do justice to the sagacity displayed by the 

 Messrs. Adams in bringing together and grouping the species of the 

 genus Terebra according to their natural affinities. Before we had 

 consulted their work we had arrived at nearly similar conclusions. 

 It is useful and even necessary to multiply, as much as the characters 

 permit, the subdivisions, when so great a number of species have to 

 be arranged. By means of this artifice it becomes more easy to 

 naturalists to determine the characters of the species they possess, 

 — an ungrateful and repulsive task, when they are obliged in every 

 case to wade through nearly two hundred descriptions. 



If we had had at our disposal all the species known we should 

 have essayed to divide them by means of the dichotomic method so 

 admirably made use of by Lamarck in the study of plants, for figures 

 can never supply the place of natural objects. Those published by 

 Mr. Sowerby in the ' Thesaurus Conchyliorum ' to accompany Mr. 

 Hind's Monograph, have the inconvenience of showing the large 

 species reduced in size and making the smaller of their natural size, 

 whilst, to show their characters well, they should have been consider- 

 ably enlarged. 



In the general catalogue of the species of the genus we shall not 

 repeat the observations already published by us in the 2nd edition of 

 the work of Lamarck, the ' Histoire Naturelle des Animaux sans 

 Vertebres,' vol. x. p. 236 and following. We applied ourselves in 

 that work to rectify and complete the synonymy of the known species. 

 An attentive comparison of our synonymy with that of Linnaeus, 

 Gmelin, and others, will show that we have not spared pains to obtain 

 more favourable results than our predecessors. We shall not therefore 



