BRITISH STALK-EYED CRUSTACEA. 415 
Hyas coarctatus, Leach. 
This species, although resembling the former in all its generic 
details, presents such a distinct difference from it as to be 
recognised at a glance. This marked characteristic consists of a 
decided contraction immediately above the gastric region of the 
carapace, which causes the anterior portion, as far as the orbits, 
to assume a curious ear-like development. The first pair of legs 
are longer, and the remaining pairs shorter and more slender in 
proportion to the size of the animal, than those of the former 
species. The carapace is of a paler red generally than that of 
H. araneus, and is tinged on the underside with white; it is also 
tuberculated. The size of the animal is, on an average, very 
much smaller than that of the former species. 
This species, as Professor Bell remarks, was discovered by 
Dr. Leach in the Firth of Forth. It is recorded, by Bell also, as 
occurring at Hastings, Worthing, Sandgate, Cornwall, Zetland, 
the Orkneys, the Loughs of Belfast and Strangford, and the coast 
of North Wales. We have obtained it from the Sussex coast, 
Milford Haven, and also from the Nore. Mr. Carrington found 
it abundant while trawling off the east coast in the North Sea. 
Those from the south coast, like H. araneus, are particularly clean 
and bright. It is also recorded as having been taken at St. 
Andrews, common; Plymouth; Shetland, the most common form 
of the higher Crustacea; Galway, common in ten fathoms; coast 
of Aberdeen; Moray Firth; and Berwick. 
It is certainly very perplexing to understand the question of 
ova, as regards the Crustacea, for this species is an example of 
the difficulty as to date of spawning. For instance, we obtained 
specimens from the Channel on January Sth, 1881, with ova 
quite mature. We also obtained others from Milford Haven on 
April 22nd, 1881, with ova not mature. In the British Association 
Report for 1866 (p. 212) it is recorded in spawn in July, October, 
and November; whilst, according to Bell, Mr. Hailstone says it 
spawns in January. We can quite depend upon our own obser- 
vations, which were carefully recorded at the time, and we have 
no reason to doubt those of other recorders. The ova much 
resembles that of the former species; they become very dark on 
approaching maturity. 
