24 G. 0. SARS. [SEC. ARC. EXP. FRAM 
scarcely exceeding half the length of the cephalic segment and rather 
densely setiferous, 1st joint much the largest, 2nd joint nearly as long | 
as the 2 succeeding joints combined, terminal part rather narrow and 
about half the length of the proximal one. Posterior antenne and 
oral parts of the structure characteristic of the genus. Posterior maxilli- 
peds, as in the type species much less robust than in the genus Tha- 
lestris, the hand being narrow fusiform in shape, with the palmar 
edge nearly straight. 1st pair of legs with both rami rather slender 
and distinctly prehensile, the outer one a little longer than the inner, 
and having the 2nd joint long and slender, last joint small and armed 
with 2 strong subequal claws accompanied by a slender seta, outer 
edge of the joint moreover carrying 2 comparatively small spines; inner 
ramus with the outer 2 joints very short, the last one armed with a 
long slightly curved claw, outside which is a much thinner setiform 
spine. Natatory legs of normal structure. Last pair of legs very largely 
developed, though scarcely to such an extent as in the type species, 
extending about to the end of the 2nd caudal segment, both joints pro- 
nouncedly foliaceous, the distal one oblong oval in form and provided 
with 4 thickish, coarsely ciliated seta, 3 of which are attached to the 
outer edge, the 4th to the inner edge near the end, the tip itself carry- 
ing 2 unequal very thin, hair-like bristles; inner expansion of proximal 
joint extending as far as the distal joint and broadly rounded at the 
end, marginal sete 5 in number, the innermost not far remote from 
the others. 
Male considerably smaller than female and exhibiting the usual 
sexual differences. 1st pair of legs with the spine attached to the inner 
corner of the 2nd basal joint falciform, incurved. Inner ramus of 2nd 
pair of legs transformed in a similar manner to that in the type 
species. Last pair of legs much smaller than in female, with the inner 
expansion of proximal joint quite short, and provided with only 3 sete. 
Length of adult female 1.30 mm. 
Remarks. — This form has been described and figured, though 
somewhat imperfectly, by Tx. Scorr in the above-quoted paper as a 
species of the genus Thalestris. According to the general form of the 
body, the shape of the rostrum, the structure of the posterior maxilli- 
peds and the great development of the last pair of legs, it is undoubt- 
edly referable to the genus Phyllothalestris, as defined by the present 
author in his account of the Norwegian Harpacticoida. It is distinguished 
from the type species, P. mysis CLaus, by a number of well-marked 
characters pointed out in the above diagnosis. 
