388 NATURAL SCIENCE. May, 1894. 



Arrangement. The classes are taken in the following order : — 

 Amphineura, Gastropoda, Scaphopoda, Lamellibranchiata, Cepha- 

 lopoda. 



The bibliography is only brought up to the commencement of 

 1892, and from internal evidence it would seem that the work itself 

 does not contain, with the possibly sole exception to be presently 

 referred to, any of the results of later researches ; but for this the 

 Societe Royale Malacologique de Belgique, and not the author, must 

 be held responsible, since it was prepared for their 1892 volume. 

 Hence it comes that Siphonaria, which Haller showed in that year 

 there were strong reasons for placing with the Opisthobranchiata, 

 here still remains in Pulmonata. On the other hand, the internal 

 nature of the shell of Ephippodonta only published, if we recollect 

 rightly, last year in the Proceedings of the Malacological Society of 

 London, has been included as an addendum under " Errata." In 

 this last connection we miss, strange to say, all reference to Dall's 

 remarkable Chlamydoconcha (1884), in which the bivalve shell is yet 

 more completely concealed by the mantle. 



On turning to the systematic part we speedily realise that Dr. 

 Pelseneer is a " lumper," for which fact we are duly grateful ; but 

 while fully appreciating the worth of the main outlines of his classifi- 

 cation and regretting that his phylogenetic tree has not been 

 reproduced, we must, in some instances, differ from him toto ccelo in 

 respect to the arrangement of his families. To take one example, 

 what possible justification is there for the following sequence (pp. 

 96, 97) : — Paludinidae, Cyclophoridae, Ampullariidae, Littorinidae, 

 Cyclostomatidae, Rissoidae, Hydrobiidae, Truncatellidse, Valvatidae, 

 etc. ? A minor point for regret is that some of the names are not 

 those accepted by most conchologists on legitimate grounds of 

 priority — e.g., C henoptis mstead oi Aporrhais. 



It could do no harm either to allude to the fossil groups — e.g., 

 Ammonea, Hippuritidae — in their approximate position in the series, 

 more especially since the Belemnitidae and Spindirostva are cited on 

 p. 178, without, however, any mention of the fact that they are 

 no longer living forms. A paragraph, too, might with advantage be 

 devoted to the structure of the molluscan shell itself. 



The work concludes with a "Table des Matieres," which may be 

 made to do duty as a table of classification for the main groups, and 

 with an admirable index. 



The above noted shortcomings in this most excellent volume are 

 not adduced from any wish to detract from its value, or in any spirit of 

 captious criticism ; on the contrary, merely in order to point the almost 

 obvious moral that not only is it impossible for any single writer to 

 produce a satisfactory treatise on Zoology as a whole, but that it is not 

 even in the power of a specialist, however eminent in his branch, to 

 deal with it single-handed in such wise as to bring it level with the 

 modern requirements of the general zoologist, a task which can only 

 be performed with anything approaching true completeness by the 

 concerted action of several workers drawn from the museum, the 

 laboratory, and the ranks of the field naturalists. Granted, however, 

 the single worker, no one could have performed the task better than 

 Dr. Pelseneer, nor is the late Dr. P. J. Van Beneden's report on it one 

 whit too strong when he says : " Tous ceux qui s'occupent de 

 malacologie que ce soit au point de vue de I'anatomie, ou de la 

 physiologie, ou meme simplement de la Conchyliologie, y trouveront 

 des renseignements d'une importance reelle." (BV)^ 



