REPORT ON THE BRACHYURA. 
189 
Cronius ruber, are wanting in Cronius bispinosus ; tire wrist is armed with two spines 
as in Cronius ruber, the palm also has but two spines, one basal, close to the articu- 
lation with the wrist, and one on the upper margin, placed some distance behind 
the distal extremity. 
The ambulatory and swimming legs are nearly as in Cronius ruber, but the 
spine which exists in Cronius ruber, at the distal end of the posterior margin of the 
merus-joint of the swimming legs, is absent in Cronius bispinosus. Colour light reddish 
or yellowish-brown. 
?. 
Lines. 
Millims. 
Length of carapace, ...... 
8 
17 
Breadth of carapace to base of lateral epibranchial spine, 
10* 
22 
Length of a chelipede, ...... 
14* 
31 
Length of second ambulatory leg, .... 
12* 
26-5 
Two adult females were collected at Bahia in shallow water . 1 
Goniosoma, A. Milne Edwards. 
Goniosoma, A. Milne Edwards, Ann. d. Sci. Nat., ser. 4, Zool., xiv. p. 263, 1860; Arcliiv. Mus. 
Hist. Nat., vol. x. p. 367, 1861. 
Oceanus, Charybdis, de Haan, Crust, in v. Siebold, Fauna Japonica, decas i. pp. 9, 10, 1833, 
names previously used. 2 
Carapace depressed, more or less hexagonal, usually marked, as in other Portunidse, 
with raised lines, one of which is prolonged inwards from the base of the lateral epi- 
branchial tooth towards the gastric region ; the antero-lateral margins are oblique, slightly 
arcuated or nearly straight, they form an obtuse angle with the front and orbits, and are 
usually armed with five or six teeth (inclusive of the exterior orbital but exclusive of the 
lateral epibranchial tooth), one or two of which may be rudimentary. The front is 
nearly always divided into eight lobes or teeth (including the tooth at the interior angle 
of the orbit). The orbits are large, open above and have usually two fissures in the 
upper margin and another in the lower margin, the interior subocular lobe of the orbit is 
sometimes, but not always, produced and spiniform. The longitudinal ridges of the 
endostome are usually distinctly developed. The post-abdomen is composed of five or 
(rarely) of six joints (two or three of the intermediate segments being consolidated). 
The eyes are set on short, thick pedicels. The antennas have the basal joints enlarged 
1 It may be of interest to note here that in a very small male Cronius milleri from Senegamhia (length only 34 
lines, or little over 7 mm.), in the collection of the British Museum, the submedian and external frontal teeth are 
confluent, as in Cronius bispinosus, hut in this specimen the four spines of the palm of the chelipedes are all perfectly 
distinguishable. I have examined a small male example of Goniosoma bispinosum from Brazil, in the British Museum, 
from the collection of my late grandfather, J. Miers, F.R.S. 
2 It should be noted that the name Charybdea used in 1809 by Peron and Lesueur, is spelt somewhat differently 
from de Haan’s designation Charybdis ; I think it better, however, to retain Milne Edwards’ designation for the species 
of this genus, which has heen generally adopted. 
