Copepoda taken in the West of Ireland. 133 



animal. Anterior antennae five-jointed, sparingly setose, very 

 minute, the basal joint excessively dilated and produced an- 

 teriorly into an overlapping hood-like beak ; posterior antennae 

 simple, biarticulate (*?), the second joint armed with six strong 

 spines, one of which is very long. Mandibles extremely 

 small, with a small bisetose palp. First pair of feet short and 

 thick : internal branch one-jointed, and bearing two strong 

 terminal spines, one longer than the other ; external branch 

 three-jointed, bearing at the truncated apex of the last joint 

 two spines similar to those of the inner branch, and also two 

 very long curved seta? : second, third, and fourth pairs of feet 

 having both branches triarticulate and nearly equal, more 

 slender than the first pair, each joint bearing at its apex a sub- 

 verticillate series of sharp slender spines. Abdominal segments 

 beset round the posterior margins with fine spine-like seta?, 

 the last two cut into rectangular notches. Caudal segments 

 very small, each bearing one large and two small setae, the 

 larger ones curved, their anterior halves dilated and spathulate. 

 Colour dark vinous red ; skin excessively thick and tough. 

 Length 3V of an inch. 



The habitat of this remarkable species is amongst the black 

 peaty mud of the upper end of Roundstone Bay, near high- 

 water mark. It is to be regretted that the specimens were 

 not noticed until after the mud in which they were taken had 

 been completely dried ; had we been able to preserve them in 

 spirit it is possible that more accurate knowledge of the mouth- 

 apparatus and some other organs might have been obtained. 

 As things stand we have been unable, with the most careful 

 dissection, to find any trace of maxillae or maxillipeds except 

 (doubtfully) of a very feeble posterior maxilliped, neither have 

 we seen any trace of a fifth pair of feet. The remarkably short 

 and thick limbs of this little creature, together with its flattened 

 ventral surface, its short, stout, and dilated tail-setae, and 

 general absence of delicate setose encumbrances, seem to fit 

 it admirably for the sort of locality in which it was found, to 

 which and similar situations it is probably exclusively con- 

 fined. 



Genus Haepacticus, Milne-Edwards. 



1. Harpacticus chelifer (0. F. Miiller). 



On weeds in Westport Bay, Valentia Harbour, and in 

 brackish pools near Clifden. 



2. Harpacticus fidvus , Fischer. 



Frequent in pools at and above high-water mark : coasts of 

 Galway and Great Isle of Aran. 



