115 
of a new Irish Crustaceous Animal. 
when looked at from above a crescent form, equidistant from 
the cornea ; when examined from the side it presents an irregular 
lozenge. 
Immediately interior to and beneath the eyes arise the superior 
pair of antennae, from the outer sides of a rectangular mesial pro- 
jection from the head of the animal forwards. They are elongate, 
robust, subconic, and as if jointed ; and have their apices each 
with a little appendix carrying curved hairs, and another internal 
to it bearing a long waved spine and a shorter straight one. They 
are a little depressed, and stand nearly directly forwards, a short 
way removed from the rostrum. 
Beneath and exterior to these, and curving somewhat outwards, 
will be found the next pair of antennae, with an origin somewhat 
anomalous. They arise very far back, behind and exterior to 
some of the manducatory apparatus, and pass forwards nume- 
rously jointed nearly as far as the extremity of the rostrum. 
They are, like the last, depressed ; and the last joint, which is very 
long, extending from the base of the superior antenna, is a short 
■way from its base turned, and sends oft" an articulated offset, 
which is half as long as the remaining portion of the antenna, and 
ends with two spines ; after this bifurcation the larger portion of 
the joint diminishes gradually in thickness, is slightly waved, 
arches outwards, and ultimately ends in two pinnate spines. A 
few minute hairs extend backwards a little way from the apex. 
The mouth seems composed of an upper lip and three pairs of 
members placed in progressive order. 
The material forming the lip extends forwards, then arches 
downwards anteriorly and laterally so as to form a hollow scoop, 
nearly fixed in position, having scarcely any motion, and seeming, 
in consequence, rather intended as a protection to the mouth, or 
throat, than an organ actually used in seizing food ; its free edge 
is furnished with very minute spatulate toothed hairs. Beneath 
the base of this lip is articulated by one angle, the first pair of 
manducatory appendages, trapeziform, reddish ; the anterior and 
superior edges nearly straight and of equal lengths ; the posterior 
longest and waved ; the anterior short, with three spines superiorly, 
and also waved so as to form a prominence at the angle opposite 
to the articulation. The gullet seems to have its position imme- 
diately above these appendages; but the specimen having unfor- 
tunately been dried on card, this part had so much collapsed as 
to render it impossible to be distinctly traced. The viscera for 
the same reason must be passed over unnoticed. 
Behind and quite free from the play of the last-described bodies 
VOL. II. K 
