4l6 JOURNAL OF CONCHOLOGY. 



compares the former to the kernel of a plum (prunum), the 

 latter to that of a date. In the ' Museum fur Naturkunde,' at 

 Berlin, there are specimens given by Pallas himself, who died 

 at Berlin in 1811, a year after the foundation of the university 

 and its zoological collections in Berlin, and these specimens 

 answer very well to the description of both the fluviatile and 

 marine form, differing in size, relative breadth, sharpness of the 

 keel, curvature of the beaks, and in colour as much as do speci- 

 mens which are collected now on the Havel river near Berlin ; 

 there can be no doubt that all belong to one species. It is true 

 that Pallas mentions the characteristic septum at the close of 

 the whole description immediately after the distinguishing 

 features of the form fluviatilis, but I am convinced that it is 

 meant for both forms, as the preceding words — ' natibus acutis 

 deorsum inflexis ' — for fluviatilis correspond to the last words 

 for marimis — ' nates acurninatce subdeflexae.' Bourguignat's 

 surmise that the marine form described by Pallas was Mytilus 

 edulis, is contradicted by the description itself, which distin- 

 guishes it expressly from Mytilus edulis. I think, therefore, 

 that there is no reason to oppose the specific name polyviorpha. 



Wollaston's 'Testacea Atlantica.' — On the cover is 

 a notice offering for sale the collection of shells of the late 

 T. Vernon Wollaston, the author of 'Testacea Atlantica.' 

 This collection constituted the basis of the work, and was 

 formed by Mr. Wollaston with the assistance of Lowe, Paiva, 

 and others. It comprises about 380 recent and 74 sub-fossil 

 species, besides numerous varieties. The shells from each 

 island are kept separate to show the variations thus occasioned. 

 They are all contained in carefully-labelled glass-topped boxes, 

 and as a typical and well-selected geographical collection, 

 would be most valuable for reference in any public museum. — 

 E. L. Layard. 



J.C., vii. , Oct. 1894. 



