﻿May, IS 54.] elliott society. 11 



Note. — Since writing the above, I have seen the text and plates of the 

 Crustacea of the Exploring Expedition under Capt. Wilkes, and can now 

 (Feb. 1856) quote another allied species, the P. Boscii of that work. It 

 is, however, distinct from the P. Boscii of Savigny, and I would propose for 

 it the name of its describer, Prof. James D. Dana, and call it P. Dance. The 

 three species will form one section of the genus, and may be characterised 

 thus : 



§ § Carapjix transversely rugose, with piliferous ridges. 



1. P. galathina, Bosc. The piliferous ridges nearly continuous across the 

 carapax ; a spine on the carapax behind the exterior angle of the eye: anterior 

 edge of carpus with five (rarely four or six) teeth, the anterior one forming 

 the angle, posterior edge with several spines; hand one-half broader than the 

 carpus. 



Color, cherry red; length about 0.5 of inch. Southern Atlantic Coast of 

 United States. 



2. P. Dance, (P. Boscii, Dana. Crust. Explor. Exped. page 421, pi. 26, 

 jig. 11.) The piliferous ridges nearly continuous across the carapax ; no spine 

 on the carapax behind the eye; anterior edge of carpus with four teeth, the 

 anterior one at a little distance from the angle formed at the articular edge, 

 which is truncate, posterior edge with a few spines: hand nearly twice the 

 breadth of carpus. 



Color, cherry red; length about 0.9 of inch. Pdo Janeiro and Coast of 

 Brazil. 



4. P. Boscii, Savigny. The piliferous ridges interrupted or broken up 

 into numerous short curved ridges, convex forwards; a spine on the carapax 

 behind the External angle of the eye; anterior edge of carpus with four teeth, 

 the anterior one at a little distance from the angle, articular edge festooned 

 with three obtuse teeth, and a sharpe spine at posterior angle, the posterior 

 border with spines : hand about as broad as carpus. 



Color, : length about 0.4 of inch. Coast of Egypt, 



4. P. armata. Plate I., fig. 4, natural size. 

 Synonyme. P. armata, Gtbbes, Proc. Amer. Assoc., vol. 2, p. 190. 1850. 

 Description. — Carapax of nearly equal length and breadth, nearly smooth, 

 but exhibiting, under a lens, minute, piliferous lines ; front not trifid, middle 

 portion prominent, lateral portions rounded ; eyes prominent, as also in the 

 last species, outer angle of orbits obtuse: at a little distance behind it, on 

 the edge of the carapax, an acute spine, from which an indistinct border runs 

 back; exterior antenncB with filament about twice the length of carapax. 



Anterior feet nearly equal, right somewhat the larger; carpus about f 

 length of body, twice as long as broad, anterior edge with three acute teeth, 

 posterior edge with four or five small spines beyond the middle ; hand subtri- 

 angular in outline, lower or outer edge serrulate with minute spines; upper 

 surface, as also that of carpus, covered with minute granulations, sometimes 

 becoming short ridges. Posterior feet, the three first pair with the upper 



