276 CRABS OF THE FAMILY PERICERIDA—RATHBUN, 
EXTRACT FROM THE UNPUBLISHED REPORT OF DR. WILLIAM STIMPSON, 
ON THE CRUSTACEA OF THE NORTH PACIFIC EXPLORING EXPEDI- 
TION, 1853 TO 1856. 
Tiarinia cornigera ‘ Latreille). 
Our specimens differ from those described and figured by Dana in 
having, at the summit of the intestinal region, one very large and two 
inconspicuous tubercles, instead of three of equal size. They are also 
much larger, some being nearly 2 inches in length. 
They are found on the reefs at low-water mark, and were collected 
at the Amakirrima Islands by the officers of the steamer John Hancock, 
and by myself at Loo Choo and Ousima. 
Tiarinia depressa Stimpson. 
(Plate x1, fig. 1.) 
=} 
Carapax in shape much like that of 7. cornigera; proportion of 
breadth to length, 1:1.5; form depressed; upper surface with tubercles 
less numerous and more flattened than in the cornigera. There is é 
small marginal spine on each side at the branchial region, above which 
an are of four depressed warts extends around the side; the first (pos- 
terior) one largest and placed a little behind the level of the tritubercu- 
lated cardiac protuberance; the fourth and smallest is near the anterior 
extremity of the branchial region, with a still smaller one before it. A 
submarginal channel of some depth passes around behind, above the 
intestinal region. Posteriorly, at the upper or intestinal Inargin, there 
is a subtriangular median tubercle, with a smaller trilobate one on 
either side of it; on the lower margin there are four small tubercles. 
On the stomachal region there are three warts in the median line, 
the anterior one smallest and placed some little distance before the 
others, with a wart on either side of it; behind the posterior one there 
are two warts placed close together. The ambulatory feet are depressed, 
smooth above, their edges not spinulose, but sparsely fringed with 
stout clavate sete. Only one specimen of this species was taken, a 
sterile female, the dimensions of which are: length, 0.77; breadth, 0.52 
length of a foot of second pair, 0.67 inch. 
In the characters of the rostrum, orbits, ete., our species much re- 
sembles 7. cornigera. The tooth at the external angle of the basal joint 
of the external antennie is, however, less prominent than in that species 
and the rostrum curves upward at its slender tip, where the horns are 
slightly divergent. It is more depressed than 7. tiarata; the forks of 
the rostrum are less divergent; the prieorbital spine less prominent, 
and is wanting in the wooly hairs characteristic of that species. 
The specimen was taken at the Island of Ousima, which forms one 
of the chain connecting southern Japan with Loo Choo. 
