Macropbdia lYhalangium. 



263 



joint the most strongly so. — Feet, First pair of legs shorter 

 and scarcely thicker than the others, didactyle (two-fingered), 

 and equal ; the internal margins of the fingers toothed ; the 

 second pair longest ; the third, fourth, and fifth pairs shorter 

 and nearly equal in length ; claws somewhat arcuate, the most 

 so in the fifth pair. All of the legs covered with strong hairs 

 or bristles. 



Of this crab I have found three specimens, all males, 

 among some sertularias brought to shore by the trawl net. 

 The shell of the largest of them measures about \ in. in 

 length. If this species of Hyas, as I take it to be, be unde- 

 scribed and unnamed, the epithet serratus may with propriety 

 be appropriated to it. 



Ord. Brachyura, Fam. Macropodiadae [Gen. Macropodia, Sp. ? Phalan- 

 gium, in a young state]. (Jig. 27.) 



a, The outer antenna ; b, the external foot-jaw ; c, the abdomen. All the figures much magnified. 



Description. — - A male. External antennae (a) half the 

 length of the body, distant, setaceous, inserted at the sides 

 of the rostrum, before the eyes ; first joint very short, and 

 thicker than the second, which is about twice its length ; 

 third joint narrower than the second, of the same length as 

 the first ; the remaining joints elongate, the last subulate. — 

 External double palpi (b) with the first joint of their inter- 

 nal peduncle notched at its external apex for the recep- 

 tion of the second joint, which is rather shorter and suboval, 

 its inner margin fringed with hairs; palpi 3-jointed, hairy. — 

 Shell subtriangular, tuberculated, rostrated in front with a 

 very short rostrum, which is bifid, its segments sloping. 

 Anterior part of the shell with two spines, the one behind 

 the other, the anterior one very small ; the posterior part of 

 the shell with one prominent spine in the same line. — Eyes 

 not thicker than their peduncles, which are very long, thick, 

 and swollen; not retractile within their orbits. — Abdomen 



