PORTO RICAN ISOPOD A . 
165 
men narrower than last segment of thorax, but not abruptly so; the first 5 segments equal in length and 
successively slightly narrower; collectively about as long as sixth thoracic segment; lateral margins 
rounded, somewhat produced posteriorly. Telson about as broad as long, slightly narrower than fifth 
segment of pleon, hilobate posteriorly. 
Peduncle of antennule as long as head, first joint stout, longer than other 3 joints combined, 
second joint not half as long as first, 2 following joints successively shorter; 2 flagella of equal length, 
and longer than peduncle, the outer somewhat stouter, with 17 joints, inner flagellum with 15 joints. 
Antennae about two-thirds as long as antennules; peduncle short, consisting of 5 joints, first and 
second joints stout, second furnished with a scale beset with long setae, last 3 joints short. Flagellum 
about as long as flagella of antennule, consisting of 13 setiferous joints. 
Mandibles stout, with a 5-dentate cutting edge and a 3-jointed palp. First maxillae tipped with 
a number of stout brown spines. Maxillipeds with a stout 4- join ted palp, of which the second joint is 
very large and stout. 
Details in relation to the oral parts are not known, as there was but one specimen, mounted in 
balsam and not dissected. 
Thechelipeds in the female are long and slender, the fifth joint being the longest and the second 
almost as long, but stouter. The third joint is prolonged distally into a curved process .furnished with 
5 or 0 long hairs on the convex margin; the sixth joint, with the seventh, constituting a slender chela; 
no molar tubercles; curved margin of “thumb” of sixth joint with a row of slender bristles; a row of 
blunt spines on cutting edge. 
The second pair of limbs have the joints stout and furnished with strong spines. The second 
joint or basis has 5 or 6 stout curved spines on its outer margin. It is longer than the other joint's. 
The terminal claw is flanked on each side by a strong spine attached to sixth joint. There appear 
to be but 5 free joints to this and the following limbs, hut this appearance may be due to defects in 
the mounting; following pairs of limbs more slender, the last pair having a second joint almost as 
long as all the rest, and with an oblique row of small spines near distal end of posterior face of sixth 
joint. 
There are 5 pairs of pleopods, with both branches 1 -jointed. 
Uropods biramous, the inner ramus with about 50 joints; outer ramus less than one-half as long, 
with about 25 joints. The joints of both are of irregular length. 
One specimen, female, from station 0079, 20 fathoms, 6 mm. by 1.4 mm. 
TANAID7E. 
Reptochelia incerta, new species. 
Bod)' of female elongate, about five times as long as broad, slightly narrower in posterior part of 
thorax. 
Head narrower in front, at base of eyes about two-thirds of greatest width, about 1.2 times as 
long as broad, length about equal to first 3 thoracic segments, slightly produced between bases of first 
antennae. The first 3 segments of thorax subequal, last 3 about one-third longer and subequal. 
Abdomen about 2.5 times as long as last thoracic segment, than which it is slightly broader; first 4 
segments about equal to one another, the fifth segment slightly longer, the sixth or terminal segment 
longest, rounded posteriorly with a blunt process in the median line. 
Eye-stalks well developed, nearly as wide as bases of first antennae, by which they are partly 
concealed in dorsal view; first, antennas 4-jointed, first joint stout, much longer than other three, 
second and third joints equal, fourth joint rudimentary, somewhat obliquely attached to third and 
furnished with about 3 long bristles, third joint also furnished with bristles at its distal end; second 
antennae about as long as basal joint of first antennae, 5-jointed, fourth joint longest, about equal to 
second and third joints together, second joint with a stout spine on inner distal angle. Mandibles 
with a tridentate cutting edge and a large molar process; first maxillae terminated bv a tuft of strong 
spines, palp with 2 long seta;; maxillipeds with large basal joint and a well-developed, strongly 
setiferous palp. Chelipeds stout, with 5 free joints; ventral margin of penultimate joint not strongly 
curved at base; thumb rather short, measured from base of dactylus about three-fourths the width of 
propodus; second thoracic limbs with the ultimate joint somewhat longer than the penultimate 
