PARACRANGON AREOLATA. 129 
Paracrangon areolata Fax. 
Plate XXXIV. 
Bull. Mus. Comp. Zoél., XXIV. 200, 1893. 
Body robust, integument indurated, keeled and sculptured. Rostrum 
long, acute, strongly upturned, laterally compressed, superior margin entire, 
inferior margin armed with two spines, one long one near the base above 
the eyes, and one small one near the tip. A prominent carina, continuous 
with the rostrum, extends the length of the carapace in the median line; it 
is armed with four spines, three of which are on the gastric region, one 
(obsolescent) on the cardiac region. Orbit incomplete, bounded externally 
by a slender spine. Outside of, and just below the base of the second an- 
tenna the antero-lateral angle of the carapace is drawn out into another 
rather stouter spine. Just behind this, and from a little higher level, 
a strong, sharp flattened horn is directed outward, forward, and a little 
upward; this horn is broad at the base, and furnished with a low carina 
above, which is continuous with a rounded ridge, which runs inward to the 
external orbital spine. A longitudinal carina on each side of the gastric 
region, armed with a small spine a little way behind the middle; from this 
spine another ridge runs upward and inward, meeting the median carina at 
the base of the third spine. The branchial regions are traversed by a series 
of ridges which anastomose in such a way as to divide these regions into a 
number of cells of various sizes, and they are armed with three small spines, 
the anterior of which is the largest. The arrangement of these branchial 
ridges and spines will be understood by a glance at the figures on Plate 
XXXIV. The hepatic region is much inflated. 
The abdomen is ornamented with a low carina, most conspicuous on the 
third segment, and on the sixth where it is double. There is also an in- 
distinct and interrupted carina on each side, at the base of the pleure. The 
pleuree of the abdominal somites are acuminate, the posterior ones longer 
pointed than those in front; each abdominal somite except the first is fur- 
nished with a transverse median ridge, interrupted in the middle ; on the first 
segment this ridge is confined to the pleure. There is a small spine at the 
base of the hind margin of the pleure of the fourth and fifth somites. The 
sixth somite has two pairs of lateral spines (the posterior pair the larger), 
and another pair at the hind end at the base of the telson. The telson is 
long and acute, with a pair of longitudinal ribs on the dorsal side ; two pairs 
17 
