388 NATURAL SCIENCE. December. 



to the distribution tables at the end of Part 11. shows how often half- 

 a-dozen species occur at the same horizon. The author would have 

 rendered good service had he dealt at some length with the varietal 

 forms, and the connection between species which could be established 

 by them. 



The genus Anthvacomya is regarded as closely related to 

 Carbonicola on the one hand, and the Mytilidcs on the other, and if not 

 byssiferous in the adult, at least with a byssiferous ancestor or 

 byssiferous fry. Sixteen species and four varieties are recorded. We 

 have already alluded to the unsatisfactory nature of four species, and 

 may mention in passing that the author admits the single specimen 

 upon which A. obovata is founded "may be a deformity or even a 

 hybrid." A form previously described as A. cavinata is now placed as 

 a variety of A . minima, since a series of intermediate forms completely 

 connects the two. The species oi Anthvacomya are well defined on 

 the whole, and there is an absence of that provoking, because not 

 fully understood, tendency of one species to slide off into another. 



In discussing the relationships of Naiadites (Anthracoptera), on 

 p. 127, the author omits to contrast or compare it with the genus 

 Anthvacomya, although previously (p. 123) he has admitted a very close 

 resemblance in both crushed and perfect examples. The difference 

 upon which he relies in distinguishing the two genera, i.e., the position 

 and shape of the umbones is one of degree rather than of structure. 

 On the whole, there is a much closer approximation in Naiadites to the 

 Modiola and Mytilus type, although in one or two species even the 

 author has failed at first to distinguish the genus. Eight species of 

 Naiadites are described, two of which are new. 



It is possible that the author has allowed several species to stand 

 against his better judgment, for fear he should be thought iconoclastic, 

 since he is well aware, for example, of the close relationship between 

 N . cavinata, N . modiolavis, and N . tviangiilavis, and considers it would 

 be perfectly justifiable to make them all into one species, a sentiment 

 with which we cordially agree. We would go one step further, and 

 put N . clongata as a variety of N. modiolavis, from which it would 

 seem to have been derived by way of N. tviangulavis. 



A series of diagrammatic sections forms the closing part of the 

 monograph, and serves to indicate the stratigraphical position of the 

 various species. 



Dr. Hind would add considerably to the value of a succeeding 

 monograph if he described the shell with greater uniformity. For 

 want of this it is often extremely difficult to compare a couple of 

 descriptions, or determine their relative value. The figures are good, 

 but, if anything, too numerous ; thirty-six figures, for example, of C. 

 aquilina occur upon one plate. 



Notwithstanding the various objections here raised, and the signs 

 of great haste shown by the Monograph, we welcome it as a needed 

 contribution to the literature of the Coal-Measures, and as likely to 

 incite further study of the MoUusca of the series. H. B. 



The Record of Big Game. 



" Records of Big Game : containing an Account of their Distribution, Descriptions 

 of Species, Lengths and Weights of Horns, and Field Notes." Square 8vo., 

 pp. xvi. and 325, Illustrated. London ; Rowland Ward, 1896. Price 30/- Nett. 



The present is a record-making age, and it is therefore no matter of 

 surprise that Mr. Rowland Ward's " Horn Measurements " has 

 reached a second edition within the comparatively short time of about 



