37 
of a new Irish Crustacecus Animal. 
ceeding backwards, and having articulated to the apex superiorly 
the third joint, which is similar in form, of nearly equal dimensions, 
placed erect, and supporting externally a minute fourth joint : the 
fifth is large, tumid in its middle, and with two minute articulated 
processes which give origin to pencils of long, curved, hairy spines. 
Behind and between these appears a singularly formed body, flat- 
tish, placed longitudinally, sub-quadrangular, and with stiff spines 
passing forwards and backwards, and from near the posterior in- 
ferior angle a large elongate process, partially articulated to it, 
which proceeds downwards and forwards, spined at its apex, and 
carrying near its base an irregularly lunated body, with strong 
waved spines passing backwards from its horns. In the female 
specimens I detected behind the above another smaller appendage, 
also quadrangular, with long waved hairy spines, directed forwards 
and entangling with those of the last described body, and with an 
elongate articulated spined process from its inferior angle. I do 
not know whether it is to be found in the remaining specimens ; 
but, from the exact similarity of the more obvious pieces, I have 
every reason to expect its existence in them. The last part, con- 
nected in any way with the organs of the mouth, lies exterior to 
that described above, and lies immediately beneath the posterior 
angle of the large ring of the body ; it is very large, irregular, 
curved forwards with traces of articulations, the anterior margin 
being divided by clefts into processes, which sustain at their apices 
one or two long, coarse, hairy spines, arched upwards near their tips, 
and obviously intended to entangle the minute objects which serve 
as food to the animal. It may be named a thoracic foot. 
'I'lie swimming feet are four pairs : the fourth joint of each is 
Hat and dilated backwards so as to be broadly triangular ; the la- 
mellate joints, which seem three in number, have two or three 
strong short hooks articulated externally, and flat-toothed lances 
internally. The last pair of feet are unlike each other and dis- 
similar in the sexes, if I be correct in supposing those to be 
females which have the undilated antenna. In the male, four arti- 
culations of the left foot project beyond the testa; the first small, 
somewhat elongate and curved ; the second large, tumid, rounded 
posteriorly ; the third longer, somewhat arched, with a blunt tooth 
at the apex, posteriorly, and the articulation for the last joint di- 
rected forwards. The fourth, or last joint, is minute, conical, and 
supports a very small articulated appendage, which is armed with 
the three claws. The right foot has in the same space only three 
articulations, the two basal sub-equal, swoln posteriorly ; the last 
flat, roundish, with a blunt process anteriorly directed downwards 
