cRtrsTACEA. 275 



curved at; tips, and having between them a small hiatus when 

 closed ; the upper or mobile finger is strongly arcuated, sometimes 

 with a strong blunt tooth at base; the lower has its inner margin 

 obscurely crenulated and sometimes toothed. The first three pairs 

 of ambulatory legs are robust, the joints nearly naked and without 

 denticles or spinules, except on the inferior margins of the penulti- 

 mate joints, which have two or three spinules at or near the distal 

 extremity ; the dactyli are short, robust; and appear biunguiculate 

 on account of the considerable development of the accessory spine on 

 the inferior margin, behind which is another small denticle. The 

 ground-colour (in spirit) is yellowish j the carapace and chelipedes 

 are blotched with pink or marked with irregular lines of the same 

 colour. Length of carapace of an adult male about 4 lines (8| 

 millim.), breadth about 3| Hnes (8 millim.) ; length of chelipede, 

 when fully extended, about 8| lines (20 miUim.). 



Port Denison, 4 fms. (Ho. 122) : a considerable number of spe- 

 cimens were obtained. Specimens were also received with the 

 second collection from Friday Island, 10 fms. (No. 153), Dundas 

 Straits, 17 fms. (No. 161), Port Darwin, 12 fms., and others dredged 

 in the Arafura Sea at 32-36 fms. (No. 160). 



The description, except as regards coloration, is taken from an 

 adult male ; the coloration is perfectly preserved in one specimen 

 only, a female with ova. The larger specimens possessing both 

 chelipedes are mostly, of the female sex. In the females and 

 smaUer-sized specimens the lateral lobes of the front are often more 

 acute, the palms of the chelipedes relatively shorter, the fingers 

 meet along their inner edges when closed, and the upper finger has 

 not the strong tooth at base, &c. 



In the robust and biunguiculate dactyli of the ambulatory legs 

 this form resembles the species of Poh/onyx, but differs in the rela- 

 tively longer carapace, which resembles that of other species of 

 Porcellana. 



I refer it doubtfully to P. nitida*, which is very briefly de- 

 scribed, and differs apparently in the triangulate form of the 

 median frontal lobe, and in haying an additional lateral marginal 

 spine behind the outer angle of the orbit ; but as HasweU's types 

 were from Port Denison, at which locality specimens of the form 

 now described were taken by Dr. Coppinger, I distinguish it merely 

 as a variety. 



^ 19. Porcellana dispar, Stimpson. (Plate XXX. fig. C.) 



Pour males and two females from Port Jackson, 5-7 fms. (No. 

 104), are referred to this species, which Mr. HasweU (Cat. p. 149) 

 observes is very common at this locality. He also records it from 

 Port Stephens. 



Stimpson's description agrees very weU with the adult males, but 



* Vide Hafiwell, Catalogue, p. 148 (1882). 



T 2 



