new and rare Crustacea from Scotland. 461 
are slender; the outer branches are elongate and strongly 
spiniferous ; the second joint is rather shorter than the first 
and only two thirds the length of the last joint; the two- 
jointed inner branch does not reach to the end of the second 
joint of the outer branch ; the first joint is rather stouter than, 
but little more than half the length of, the second joint; the 
second joint bears four sete—the two apical and one of the 
marginal are very long, but the other is short (fig. 7). The 
third and fourth pairs are also slender and with short inner 
branches; in the fourth pair the first joint of the inner 
branches, which only reach to about the middle of the second 
joint of the outer branches, is so short as to be almost rudi- 
mentary (fig. 8). In the fifth pair the inner produced portion 
of the basal joint is somewhat cone-shaped and bears three 
moderately long and stout plumose setee on the inner margin 
and two smaller sete at the apex; the apex of the basal joint 
only reaches to about half the length of the secondary joint ; 
the secondary branch is elongate-ovate in form, being nearly 
three times longer than broad; the apex is lengthened into a 
narrow process, from the end of which springs a moderately 
long seta; on each side of this there is a subapical seta, also 
of moderate length, while three other sete spring from the 
distal half of the outer margin (fig. 9). Caudal stylets 
narrow and about equal in length to the last abdominal 
segment. 
Habitat. Port Erin, Isle of Man; and near the mouth of 
the River Alness, Cromarty Firth ; rather rare. 
Remarks. This Laophonte has a superficial resemblance to 
L. denticornis, T. Scott, but on closer examination it was 
found to differ very markedly, not only from that species, but 
from any other Laophonte known to us. 
Idya longicornis, sp. n. (Pl. XVII. figs. 10-17.) 
Description of the Species.—Female. Length 1°7 millim. 
(75 of an inch). ‘This form resembles [dya furcata, Philippi, 
in general appearance, but is larger. The antennules, which 
are eight-jointed, are very long and slender; the first four 
joints are elongate, especially the third and fourth, which are 
nearly of equally length, the fourth being slightly longer than 
the other; it is also longer than all the last four taken 
together. The formula shows the proportional lengths of all 
the joints— 
Proportional lengths of the joints.. 80.40.45.47.7.10.8.18 
Number of the joints ............ Pewee A) Ads Gi BFF 
