REPORT OR THE BRACHYURA. 
85 
Subgenus Nemausa, A. Milne Edwards. 
Nemausa, A. Milne Edwards (genus), Crust, in Miss. ScL au Mexique, p. 80, 1875. 
„ Miers, tom. cit., p. 666. 
Carapace subpyriform, much longer than broad ; spines of rostrum well developed, 
slender, acute. Epistoma scarcely transverse. Basal antennal joint with a long spine at 
its antero-external angle. Merus of the exterior maxillipedes produced at its antero- 
external angle. Chelipedes of moderate size ; palm rather slender, compressed. 
M. A. Milne Edwards refers the following species to this genus, or subgenus as 
I prefer to regard it : — 
Nemausa rostrata, A. Milne Edwards. Gulf of Mexico and Caribbean Sea (to 
163 fathoms) ; Bermuda. (The name rostrata has been used by Bell ( vide 
infra ) for a true Mithrax). 
Nemausa spinipes (Bell). Galapagos Islands; (Cape?) St. Elena, to 16 fathoms. 
Mithrax ( Nemausa ) rostrata. 
Nemausa rostrata, A. Milne Edwards, Crust, in Miss. Sci. au Mexique, pt. 5, vol. i. p. 81, 
pi. xvii. fig. 4, 1875. 
Bermuda, shallow water (a male and female). 
In these specimens the spines of the rostrum are somewhat shorter and the tubercles 
of the carapace are less symmetrically disposed than in A. Milne Edwards’ figure ; in the 
smaller specimen there is but one spine upon the sides of the branchial regions, the others 
being represented by rounded tubercles. 
6 • 
Lines. 
Millims. 
Length of carapace and rostrum, 
10* 
22 
Breadth of carapace, .... 
8 
17 
Chelipedes (deficient). 
Length of first ambulatory leg, 
13 
27-5 
Subgenus Mithrax. 
Mithrax and Mitlvraculus , Miers, tom. cit., p. 667, 1879, et synonyma. 
Carapace very broad and depressed, usually transverse ; spines of rostrum very short 
or obsolete. Basal antennal joint very much enlarged, with short spines at the distal 
extremity. Chelipedes often large, with the palm compressed and more or less dilated. 
1. Carapace with the branchial regions not dorsally sulcated, the lateral margin 
usually armed with spines. 
