OTUS. 
223 
A MPHIP OP A . PH OX IDES. 
NA T ATOM A. 
Genus— OTUS. 
Otus. Spence Bate, Cat. Amph. Crust. Brit. Mus. p. 125. 
Generic character. Cephalon anteriorly produced. Pereion 
distended. Pleon compressed. Antennae simple. Third pair 
of siagonopoda unguiculate. First pair of gnathopoda chelate ; 
second subchelate. Posterior pair of pleopoda biramous, 
Telson single. 
The head is anteriorly produced. The body is much 
distended, while the tail is considerably narrowed. The 
antennae are subequal in length, the upper being the 
more robust, and not furnished with a secondary ap- 
pendage. The mandibles possess a three-jointed ap- 
pendage. The maxillipedes terminate in a small nail. 
The first two pairs of legs are small, and of nearly 
equal size, the first terminating in a distal double- 
fingered claw ; the second, which is rather stouter than 
the first, being only subchelate. The coxae of the four 
anterior pairs of legs are deep, the fourth being also 
very broad, and posteriorly deeply excavated to receive 
the anterior lobe of the coxa of the fifth pair. The 
walking legs are short and strong, and furnished with 
sharp fingers. The three posterior pairs of caudal ap- 
pendages are double branched, and the central tail-plate 
is single and scale-like. 
This genus bears a near resemblance to Iphimedia , but 
is distinguished from it by the form of the maxillipedes, 
and by the character and proportions of the first two 
pairs of legs. 
The near approximation of the characters of the two 
genera suggested the name of the son of Iphimedia as 
being appropriate for the present more recently disco- 
vered form. 
