626 On a supposed new Gemis and Species. 



clianged tlie name of the former to //. fulva, whilst no allusion 

 to the latter appeared in the text ; but in the explanation of 

 the plate, now renumbered xiv., figures 80 and 81 are called 

 Helix fulva. Brown had, therefore, seen and recanted his 

 error, but to avoid spoiling his plate refrained from erasing 

 the figures 80 and 81. 



Despite the yet further complication introduced by Gray in 

 1847 (Proc. Zool. Soc. p. 173) when he made " TrocJiidea 

 [sic]. Brown, 1827,^' a subgenus of Tlieba, and cited as type 

 " Helix olegans^'' we consider tli;it Brown's Trochoidea cannot 

 be taken to refer definitely to eitlier H. fulva ov 11. elegans, 

 and should be allowed to disapjiear from moUiiscan literature. 



LXV. — Preliminary Account of supposed neio Genus and 



Species. By the Rev. Thomas R. R. Stebbing, M.A., 



F.R.S. 



Prohlemaearis spinetum, gen. et sp. n. 



Though preliminary descriptions are, as a rule, objection- 

 able, the present instance is justified by the fact that the full 

 account, with the illustrations already prepared, cannot hope 

 for early publication. 



For the genus, it may be said that it belongs to the 

 Carides iu Borradaile's 'Classification of the Decapod Cius- 

 tacea,' 1907, without exactly fitting any of his subdivisions. 

 It appears to be an oversight in the Classification that the 

 Pandaloida have the wrist of the second legs " divided into 

 two or more joints," while the " Thalassocarin?e," a subfamily 

 of the Piuidalidaj, have the "second wrists undivided.'" 

 Borradaile's further 'Notes on Carides' in 1915 do not 

 allude to this ambiguity, nor is it explained in the additional 

 notes (Tr. Linn. Soc. vol. xvii* 1917). 



The name adopted for the new geaus refers to the obscurity 

 of its place in classification, and the specific name alludes to 

 the multiplicity of conspicuous spines in many parts of the 

 organism. The palpless mandibles have the cutting-edge, 

 spine- row, and a molar-edge iu a contiimous line. Flagellate 

 exopods are present on all appendages from first maxillipeds 

 to at least the fourth perajopods. Third maxillipeds slen- 

 derly pediform. First and second perjeopods with small 

 chelee and undivided wrist. 



This form, while evidently distinct, superficially invites 

 comparison with Thalar^socaris stimpsoni. Bate {' Challenger' 

 Macrura, pi. cxvii.), noted by Balss as a larval form of some 

 unknown genus, 

 welcome. 



