150 Mr. E. J. Miers on the Plagusiine. 
Von Martens remarks (Arch. f. Naturg. xxxviii. p. 112, 
1872) that he found it impossible to find constant characters 
to separate specimens (referred by him to Plagusia squamosa) 
from Cuba, Brazil, Madeira, and the Red Sea. As, however, 
he had seen only a male and a female from the last-mentioned 
locality, and had seen no specimens of the Plagusia orientalis 
of Stimpson, it is probable that he may have overlooked the 
characters derived from the superior lobes of the ambulatory 
legs and terminal postabdominal segment in the male (vide also 
‘Preuss. Exped. nach Ostasien,’ zoolog. Theil, i. p. 22, 
1876). 
Plagusia immaculata. 
Plagusia immaculata, Lam, Hist. An. sans Vert. v. p. 247 (1818). 
Plagusia depressa, Latr. Encycl. Méth. x. p. 145 (1825); M.-Edw. 
Hist. Nat. Crust. ii. p. 98 (1837) ; Ann. Sci. Nat. (sér. 3) Zool. xx. 
p. 179 (1853) ; Dana, U.S. Expl. Exp. xiii. Crust. 1. p. 869 (1852); 
Stimpson, Proc. Ac. Nat. Sci. Phil. p. 108 (1858); nec Cancer 
depressus, Fabricius. 
In this species the carapace is more convex than in either 
of the preceding, the tubercles much depressed, quite naked, 
often almost obsolete upon the gastric and cardiac regions. 
The lobe above the bases of the second and third pairs of am- 
bulatory legs is small and not dentated. 
The series in the British-Museum collection includes speci- 
mens from Ceylon (Holdsworth), Torres Straits (Jukes), Philip- 
pine Islands (Adams), Timor Island (Rayner), Louisiade 
archipelago (Macgillivray), Sandwich Islands, Honolulu 
(Lieut. Strickland). 
According to Stimpson, specimens found on the west coast 
of Central America by Capt. Dow belong to this species. It 
inhabits the seas of China, New Guinea, and the Indian 
Ocean (I/.-Hdw.) ; the islands of Loochoo and New Ire- 
land (Stimpson); the Straits of Sunda (Dana), Nicobars, 
Shanghai, and Punipet (//edler). 
Milne-Edwards has pointed out the unsuitability of the 
name of P. depressa for this species, which is the most convex 
of any of the Plagusiine ; and as it is not the Cancer depressus 
of Fabricius, nor (probably) of Herbst, it appears necessary 
to adopt Lamarck’s name of P. ¢mmaculata, which is quoted 
as a synonym of the species by Milne-Hdwards (Hist. Nat. 
des Crustacés). 
I transcribe the following MS. note of the colours (when 
fresh) of a specimen found on the ship’s bottom, off Redscar 
Point, in the Louisiade archipelago, and now in the British- 
Museum collection :— 
“Colour pale green, mottled with reddish brown. Tarsi 
