Mr. E. J. Miers on the Plagusiine. 149 
Plagusia depressa. 
PCancer depressus, Fabr. Syst. unt. p. 406 (1775) ; Ent. Syst. Suppl. 
p. 343 (1798). 
PCancer squamosus, Herbst, Naturg. Krabben u. Krebse, i. p. 260, 
pl. xx. fig. 113 (1790). 
Plagusia depressa, Say, Journ. Ac. Nat. Sci. Phil. i. p. 100 (1815). 
Plagusia Sayi, DeKay, Zool. N.Y. Fauna, vi. Crust. p. 16 (1844) ; 
M.-Edw. Ann. Sci. Nat. (sér. 3) Zool. xx. p. 179 (1853) ; Stimpson, 
Ann. Lyc. Nat. Hist. New York, vii. p. 64 (1859). 
Plagusia squamosa, Latr. Encycl. Méth. x. p. 145 (1825); Dana, USS. 
Expl. Exp. xiii. Crust. 1. p. 868 (1852), 
Plagusia gracilis, Saussure, Mém. Soc. Phys. et Hist. Nat. Genave, xiv. 
p- 449 (1858). 
This species very closely resembles the preceding, but is 
distinguished, as Mr. Stimpson, in his “ Notes on the North- 
American Crustacea,” has pointed out, by the following 
characters. There is a series of about six prominent acute 
tubercles arranged in the form of an arc across the front of 
the gastric region; and the lobe above the bases of the second 
and third ambulatory legs is broader and regularly dentated. 
The terminal segment of the postabdomen in the male is, I 
may add, narrower, with the sides more distinctly convergent 
to the distal extremity. 
Hab. This species inhabits what may be denominated, in 
contradistinction to the Indo-Pacific, the Atlantic region. 
Specimens are in the British Museum from the Tortugas, 
Garden Key (Smithson. Inst.), Jamaica (Gosse), Madeira (Rev. 
Rh. T. Lowe, Dr. Halley, Blewitt), Brava Island (Rev. R. T. 
Lowe), St. Helena (Melliss). 
It is recorded from Charleston Harbour, South Carolina 
(Gibbes), and Brazil (Lichtenstein, fide Latreille). 
In one adult specimen from Madeira in the Museum collec- 
tion the teeth of the superior lobes of the ambulatory legs 
are nearly obsolete ; but even in this instance, in their broader 
and more truncated apices, they differ from the same lobes in 
the preceding species. 
On account of the habitat (“in mare Mediterraneo, Amert- 
cano’’), the Cancer depressus of Fabricius, Syst. Ent. p. 406 
(1775), and Ent. Syst. Suppl. p. 343 (1798), probably be- 
longs to this species; and I adopt his name for it the more 
readily as Say, in 1815, employed it for specimens from the 
coast of the United States. The figure of Herbst’s Cancer 
squamosus distinctly represents the lobe at base of the ambu- 
latory legs as dentated, and hence is to be referred to this 
species ; but as the habitat is given as “ Ost-Indien,” there 
can be little doubt that Herbst, like most later authors, 
failed to appreciate its distinctive characteristics, and united 
under one name the Atlantic and Indo-Pacific forms, 
