CRUSTACEA. 



73 



GENUS, GELASIMUS. 



" Foot-stalk of the eye long and slender, the transparent cornea 

 small. Carapace resembling that of Gonoplax, but more ad- 

 vanced in front, and less extended laterally. 



This family (by Genus) is by Dr. M. Edwards placed among 

 the Oeypodidce, but is here coupled with Gonoplax from the great 

 similarity of form and habit of the following species. 



In the history of Crustaceans by Dr. M. Edwards, no notice is 

 given of any species of this Genus as found in the European 

 seas ; and therefore I feel some hesitation in assigning to it a 

 species frequently found in the stomach of fishes taken in depths 

 varying from five to more than twenty fathoms, but of which no 

 figure is found in the works of Pennant or Leach. 



The form of the Carapace is represented by Dr. M. Edwards, 

 pi. 18, fig. 10, and consequently much resembling that of 

 Gonoplax ; but that of the present species differs from the figure 

 by that gentleman in possessing a second and well-marked hook 

 on the lateral margin a little behind the anterior angle, and at the 

 place where in the Gonoplax bispinosa there is a protuberance 

 much less marked, but giving origin to the trivial name. Both 

 claws are of equal size and less than the transverse breadth of 

 the carapace. The eye-stalks are concealed in the manner of 

 Gonoplax ; but as the carapace is more advanced at the separation 

 of the ocular cavities, when withdrawn, their extremities point a 

 little backward. 



I find but little difference in the form of the male and female, 

 and none in the proportion of the claws, though such is the case 

 for the most part in Crustaceans. I have provisionally designated 

 it G. Bellii (Couch MS and fig.) in honour of the professor 

 of Zoology in Kings' College, whose labours have been eminent 

 in this department of science." 



GRAPSIBJE. 



Genus, Planes. — Leach. 

 , , Nautilograpsus. — Edwards. 

 ,, Pachysoma. — De Kaan. 



Carapace quadrate, straight in front, rounded posteriori}-. 

 Orbits placed at the latero-anterior angles, space between the eyes 

 half the width of the carapace. First pair of legs chelate robust, 



