PARANTHURA. 163 
Genus—PARANTHURA. 
Oliska (2). Risso. Hops, 
Generic character. Like Anthura, except in the structure of 
the pleon, which has the several segments distinctly articulated 
with each other, and carries the normal number of pleopoda. 
THE animal is long, slender, and linear; the head 
distinct from the first segment of the body, the latter 
consisting of seven segments, the whole being nearly 
subequal, except the last, which is shorter than the 
preceding. The tail is short, being about one-eighth of the 
length of the entire animal, consisting of seven separate 
segments, six of which support appendages. The eyes 
are sessile and ovate. The superior pair of antenna are 
short, being about the length of the head, each being 
formed of six joints, gradually diminishing in size to 
the last. The inferior pair is longer and much stronger 
than the superior, and five-jointed, the large basal joint 
being attached to the head by a short, indistinct joint ; 
the second, third, and fourth joints gradually increase in 
length, the fourth being not quite so long as the basal 
joint; the fifth joint is nearly as long as the fourth, and 
gradually attenuated to the tip, furnished with long 
sete, and terminated by a very minute, exarticulate 
point. The three anterior pairs of legs (namely, the 
two pairs of gnathopoda and first pair of pereiopoda) 
are formed upon the same type, and terminate in a sub- 
chelate hand. The four posterior pairs of legs are more 
slender, and attached in an opposite direction to the 
anterior pair. Each of the tail appendages (or pleopoda) 
consists of two membranaceous plates for respiration ; 
M 2 
