334 Bibliographical Notices. 



I liave already pointed out the many and important differ- 

 ences wliicli there are between the two forms. A comparison 

 of ]\IacGillivray's fiojure with my own will show that they are 

 more or less dissimilar in almost every element of the struc- 

 ture. It is not the mere numher of the spines which is 

 different ; the difference in character is much more important. 

 MacGillivray's descri|)tion, "long, slender, incurved spines," 

 does not apply to those of B. distans. Their form and 

 arrangement, as shown in his figure, offer a complete contrast 

 to those of the present species *. 



It is unnecessary that I should repeat here the careful 

 comparison of the two forms which is embodied in the 

 original account of B. distans ; but I may emphasize the 

 diflferences in the avicularia, of which enlarged figures are 

 given. 



'Annals,' Feb. 1882 (p. 80 sej).). 

 Memhranipora pilosa ^ Linn., form multispinata. 



This form was referred doubtfully to .1/. pilosa, but I now 

 regard it as a distinct species which will rank as ^[. multi- 

 spinata (see the original description, loc. cit. and the figure on 

 ])late v.). 



[To be conliimed.] 



BIBLIOGIIAPHICAL NOTICES. 



Catalogue of the Type Fossils in the Woodwardian Museum, Cam" 

 bridge. "By Henry Woods, B.A., F.G.8. With a Preface bv 

 T. M-^Kenny Hughes, M.A., F.ll.S. 8to. ISO pp. Cambridge, 



1891. 



To enable biologists to be within their rights, and not to infringe 

 on those of othoi's, in giving original names to new genera of 

 animals and plants, there have been provickni published lists (and 

 very lengthy catalogues they are) of the appeUations already appro- 

 priated ; and lists of specific names are available to a limited extent ; 

 but still the recorder of a new species has to be assured whether or 

 no his specimens differ from or agree with already published forms ; 

 and to this cud it is requisite that he should see those that have 

 been already described, the jtublislied figures and descriptions not 

 being always satisfactory. 



• > rolyzoii ol' A'ic'torin,' (bx-mlc v. p. '>V2. \\. xlvi. li<:s. .". 



