LEPTOCHELIA EDWARDSII. 135 
antennz are about half the length of the animal, and 
consist of one long basal joint exceeding one-third of the 
whole length of the organ; the second is scarcely half the 
length of the first, and is followed by a series of eight 
small joints, each succeeding one being shorter than the 
preceding. These eight small articuli are furnished on 
the under side with bundles of those membranous hairs 
which we have generally considered as being connected 
with the acoustic apparatus, and therefore named auditory 
cilia, but which Dr. V. Herisen, who has given much 
attention to the subject, considers as having nothing to 
do with the sense of hearing. The two basal joints of 
this organ have not these appendages, hence we think 
that they alone represent the three joints of the normal 
peduncle. The inferior pair of antennz are very short, 
reaching but little beyond half the length of the basal 
joint of the superior pair. They are small, slender, and 
feeble organs, generally directed obliquely downwards, 
and consist of five joints, the first two of which are 
robust and short, the two succeeding long and slender ; 
the apical one minute and rudimentary. They are fur- 
nished with a few long slender hairs. The first pair 
of gnathopoda are large, strong, very long, being about 
two-thirds the length of the entire animal, and reaching 
beyond the extremity of the antenne; the three basal 
joints appear to be without the power of articulation, 
which exists most freely between the meros and the 
carpus; the carpus reaches quite to the extremity of 
the basal joint of the superior antenne ; the propodos is 
longer than the carpus, and with the dactylos forms a 
large, gaping, pincer-like claw; the infero-digital process 
of the hand is curved, and armed with two strong tuber- 
cular teeth; the dactylos is also curved and feebly 
serrated, a minute hair springing from the anterior 
