THE 



aEOLOGICAL MAGAZINE. 



No. CII.— DECEMBER, 1872. 



I. — On Orithopsis Bonneyi, a new Fossil Crustacean. 



By James Carter, M.E.C.S., etc. 



(PLATE Xlir. FIG. 1.) 



IN a paper, " On the Geology of the South Coast of England," pub- 

 lished in the Transactions of the Geological Society, vol. i., 

 2nd ser., pi. iii., fig. 2,^ p. 42, Sir H. de la Beche has figured a 

 crustacean from the Greensand of Lyme Eegis, to which he has not 

 applied any name, or given any other description than that it is "the 

 back of a singular fossil crab." The specimen is imperfect, and not 

 very accurately drawn ; but Prof. Bell, in his monograph, published 

 by the Palseontographical Society (1862), expresses his opinion that 

 it is an " unmistakeable figure " of JVecrocarcinus tricarinatus. 



A crustacean from the Gault of Folkestone is figured and described 

 by Mr. Woodward in the Geological Magazine, Vol. V., PL XIV., 

 Fig. 4, p. 259, which he regards as also a specimen of N. tricari- 

 natus. Unfortunately the anterior portion of the carapace is broken, 

 and does not exhibit the important characters of the orbito-frontal 

 region. 



The well-preserved specimen from the Greensand of Lyme Eegis, 

 figured in PI. XIIT., Fig. 1, has been recently added to the Wood- 

 wardian Museum at Cambridge, and I have a smaller one from 

 the same locality in my own collection. 



There cannot, I think, be a doubt but that the crustacean figured 

 by Sir H. de la Beche and by Mr. Woodward, as also the specimens 

 from Lyme Eegis, are all examples of one and the same sjiecies. 

 It is, moreover, evident, as Mr. Woodward observes, that this species 

 is generically distinct from Necrocarciniis Wooclwardii and N. Bechei. 

 I would add that it is equally distinct from N. tricarinatus. Indeed, 

 so far as I know, it is not referable to any described genus. I there- 

 fore propose to establish a new one, which I would designate 



1 Not fig. 1, as stated by Mr. "Woodward and Prof. Bell iu their respective 

 papers. 



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VOL. IX. — NO. CII. 34 



