44 FOSSIL MALACOSTRACOUS CRUSTACEA. 



SUPPLEMENTARY NOTICES AND COEEECTIONS. 



Xanthopsis. — Since the earlier sheets of this work have been printed, my attention 

 has been recalled to a letter from Professor Milne Edwards to Mr. Wetherell, with which 

 the latter gentleman favoured me some time ago, in which the following passage occurs — 

 " The original specimen of Cancer Leachii, described by Desmarest, has been recently given 

 to our museum, and I have thus been enabled to distinguish that species with certainty from 

 all the other Canceridse of the London Clay. It is not the Xanthopsis nodosa of M'Coy 

 (= C. Leachii of your collection), but a species of which you have only one young 

 specimen." These observations, from such a source, would appear to wholly unsettle the 

 conclusion to which I have come on the synonymy of these species ; but the fact is 

 that the two figures in M. Desmarest' s plate are evidently taken from two very different 

 specimens ; and whilst I think the observations of Professor Milne Edwards are clearly 

 applicable to the figure of the under side (see Desmarest, Plate viii, fig. 6), it is equally 

 clear to me that the other figure in the same plate (fig. 5) is taken from a specimen of 

 X. nodosa of M'Coy, which must, therefore, still be retained as a synonym of X. Leachii. 

 The former figure I should consider as representing X. bispinosa, to which it bears an 

 obvious resemblance in the form of the segments of the abdomen, and this is most 

 probably taken from the specimen referred to by Professor Edwards ; but it does not 

 appear necessary further to modify the criticism I have already made on these species. 



ADDITIONS TO THE SYNONYMY. 



Xanthopsis Leachii. 



Bronn. Index Palseont., i, p. 212. Morris. Cat. Brit. Foss., 1854, p. 116; Cat. 

 Invert. Mus. Roy. Coll. Surg., 1856, p. 1/4. 



Plagiolophus Wetherellii. 



Parkinson. Organ Rein., vol. iii, pi. xvii, fig. 1. 



Dromilites Lamarckii. 



Parkinson. Org. Rem., vol. iii, pi. xvii, fig. 7. 



Basinotopus Lamarckii, Morris. Cat. Brit. Foss., 1854, p. 101 ; Cat. Invert. Mus. 



Roy. Coll. Surg., 1856, p. 176. 





