278 Mr. W. V. Guise on a new species of Alpheus. 



outer surface of the larger pincers; in the proportions and 

 form of the anterior feet, and in other minor particulars. 



Assimilates with A. dentipes, as with Edwardsii, in the spinous 

 terminations to the supra-orbital hoods ; 



Differs, with respect to the comparative proportion between 

 the two anterior pairs of legs ; and inasmuch as the three hinder 

 pairs of legs are not armed externally with a pointed tooth. 



Having thus shown in what respects the Alpheus from Herm 

 assimilates with, and differs from, the three species above re- 

 ferred to, it remains to describe its own particular character- 

 istics, which are as follows : — 



The medial line of the carapace prolonged anteriorly into a 

 short beak : supra-orbital vaults, each furnished at the extremity 

 with a minute spine : anterior legs unequal ; the larger hand 

 having upon the upper edge two carinse, one behind the other, 

 each terminating anteriorly in a small tooth projecting forwards ; 

 two carinse upon the outer surface of the claw, the lower one 

 having a short tooth : the moveable finger not shorter than the 

 immoveable one, flattened laterally, and broad at the point : the 

 immoveable finger triangular, strong, and forming a kind of 

 socket into which the opposing finger fits by a tubercle at its 

 extremity : lesser pincer having a toothed keel upon its upper 

 edge, equal in length to the others, but thinner, narrower, and 

 much less robust : second pair of legs didactyle, slender, and 

 having the wrist many-jointed. 



Length 15 lines. 



Colour deep scarlet, except the chelse, which are mottled with 

 yellow. 



From the want of other works of reference, besides those of 

 M. Edwards and of Professor Bell, I have it not in my power to 

 ascertain whether the species now under notice has been distin- 

 guished by later carcinologists ; but I have endeavoured, I think 

 satisfactorily, to show that it cannot be identified with either of 

 the European species of Alpheus described by the former distin- 

 guished naturalist. As regards both the figure and description 

 of Alpheus ruber in BelFs 'British Crustacea,^ they having been 

 confessedly taken from an imperfect individual, found in the 

 stomach of a Cod-fish, have so little in common with my Channel 

 Island example, that, if identical with it, it must be presumed 

 that all the more marked points of agreement between them had 

 been digested away in the interior of the fish. 



In the 8th volume of ' Loudon\s Magazine of Natural History,' 

 page 272, is however a notice of a Crustacean by the late Mr. 

 Hailstone, which certainly agrees far more nearly with my ex- 

 ample than do either of those to which I have already referred ; 



