Bibliographical Notices. 317 



Germany, and also on account of his own very bad health, been 

 obliged to make an excusion to the west coast of South America, where 

 there is no doubt he will add much to our knowledge of the mol- 

 luscous animals, and it is to be hoped give us as good a work on the 

 moUusca of those seas as his very excellent one on those of Sicily. 



The present work is divided into three sections. The first con- 

 tains the general characteristics of MoUusca, with an account of their 

 systematic classification, uses, and terminology. 



The second, the systematic arrangement of the 638 genera oiMol- 

 lusca (viz. 403 Univalves, 210 Bivalves, 25 Tunicata), and 35 genera 

 of Cirripedia, with their characters, synonyma, a reference to those 

 works in which they were first described, and the derivations* of 

 their generic names. 



The third contains an alphabetical list of all the genera of recent 

 and fossil MoUusca which are not referred to in the former part ; an 

 index of the Latin and German terms used in the work and of the 

 genera and their synonyma. 



The first Part appears to be very carefiiUy executed, and contains 

 a great quantity of very interesting and novel matter. 



In the second Part all the classes are arranged nearly in the same 

 manner as in the latest edition of the Systems proposed by Dr. Gray 

 in his various Essays, and as now used in the British Museum, and 

 the greater part of the names of the genera and their synonyma are 

 evidently adopted from the List of Genera of MoUusca published by 

 that author in the Proceedings of the Zoological Society for 1847. 

 The enlargement of the Cuvierian order Scutibranchia to contain the 

 Nerites, Trochi and Turbines, as well as the Haliotidce and Emargi- 

 nulidce, is adopted, and it is placed next to the CyclobranchicB and 

 Cirribranchiata. The families proposed in the 'Synopsis of the 

 British Museum' for the year 1838 and 1840, graduaUy modified as 

 the knowledge of the animals increased until the publication of the 

 fourth volume of the 'Figures of MoUusca" by Mrs. Gray, and in 

 the Special Catalogues of Pteropods and Cephalopods, have been 

 almost uniformly adopted ; the chief alterations being the separa- 

 tion of the Olivacea from Buccinidce proposed by Dr. Troschel, 

 the placing of Siphonariacea and Acmeacea (= Tecturidce) with 

 Pectinibranchia, and the arranging of Ampidlariacea with Pulmonata, 

 — three alterations which must have arisen from Dr. Philippi's not 

 having had the opportunity of examining the animals, which we 

 are convinced he will be the first to alter when he has done so ; and 

 fortunately the country he is now engaged in exploring wiU afibrd 

 him many materials for the purpose. 



Dr. Philippi, when speaking of Dr. Gray's arrangement, observes, 

 that it has been changed from year to year. We consider this is the 

 greatest praise, for the changes have only been made by trying to 

 keep the systematic arrangement of the MoUusca on a level with the 

 rapidly progressive state of the science. 



It is an exceUeut manual, and almost the only work on the sub- 



* There are many instances where explanations are given of names which 

 were intended simply as names without any meaning, and some names of 

 this kind are corrected to make them fit the explanations given ! ! ! 



