170 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
Epimera of all the thoracic segments except the first distinct, of second and third not produced 
posteriorly, the following ones successively more produced, the last two terminating in strong angles. 
First antennae about as long as peduncle of second antennae; peduncle of two equal joints, flagellum 
slightly longer than peduncle, about 8 or 9 jointed; distal ends of segments furnished with a few short 
hairs; second antennae reaching to end of second thoracic segment; peduncle 5-jointed, fifth joint 
longest, slightly exceeding the fourth, which is as long as first three joints together. 
Mandible weak, with bifid cutting edge and 3-jointed palp. First maxilla large, robust; plate of 
first joint expanded at distal end into a somewhat quadrate curved face closely beset with papillae and 
looking like a triturating plate; third joint very stout, strongly curved with a very strong terminal 
spine continuous in contour with the rest of the joint; at base of curved portion, on inner side, a stout 
knob-like protuberance. The first maxilla is the largest and most conspicuous of the mouth parts, 
overlapping and hiding the mandible, and in the male reaching to the base of the antennae. In the 
female the terminal spine is straighter, not so continuous with the rest of the plate, and points inward 
and somewhat backward. Second maxilla 4-join ted; first two joints short and stout; second joint 
stout, decreasing distally; third joint slender and tapering, set at an angle to second joint and furnished 
at its tip with several setae, one of which is usually longer and stouter than the others. 
Maxillipeds with rather slender 5-jointed palp, more slender in male, first joint shortest, second 
joint longest, 2 to 3 times as long as first. 
First pair of thoracic limbs with fifth joint set obliquely to the plane of the preceding joints, very 
short, almost hidden on inner or anterior face, but triangular and appearing to be deeply embedded in 
fourth joint when viewed externally; fourth joint with about 4 stout spines on inferior edge, second 
limb with fifth joint longer and with slight obliquity; third pair similar but longer. Pairs 4 to 7 more 
slender, with numerous spines, the third, fourth, fifth, and sixth joints subequal. 
Uropods stout, the peduncle prolonged at its inner angle into a robust process. Inner ramus 
broad (about 1.5 times as long as broad), extending beyond end of telson; outer ramus shorter and 
narrower, extending barely beyond tip of telson; apex truncate or subbifid. 
Telson triangular, about two-thirds as long as broad, lateral margins somewhat excavated, apex 
narrow, rounded. 
Seventeen specimens from stations 6062 and 6063, 25 to 75 fathoms. Largest 8.5 Dy 3.8 mm.; 
smallest 5.5 by 2.5 mm. 
Alcirona hirsuta, new species. 
Front slightly produced and somewhat indexed between the bases of the antennules, not joining 
the epistome; eyes small, lateral, distance between two or three times their diameter. 
Body strongly arched antero-posteriorly. Epistome narrow, pentagonal. First antennae with 
2-jointed peduncle reaching to about end of fourth joint of antennal peduncle. Flagellum slightly 
shorter than peduncle, of 7 joints, first joint as long as second and third. 
Second antennae reaching to middle of third segment, with 5-jointed peduncle; first three joints 
short, fourth and fifth joints each about twice as long as third and subequal, flagellum with 17 joints. 
Mandibular palp rather robust, 3-jointed, second joint longest, second and third joints with setae. 
Maxillipeds with 5-jointed rather robust palps. 
First segment of trunk about 1.6 times as long as second, the next five equal, the seventh a little 
shorter; third segment with a few setae on lateral portion of posterior margin ; fourth, fifth, sixth, and 
seventh with complete rows becoming successively more dense posteriorly. In one specimen a very 
few hairs at side of second segment. First three pairs of peraeopods subsimilar, fourth joint broad and 
armed with several very strong spines, fifth joint very short, almost hidden in the first leg, somewhat 
longer in the second and still longer in the third. Seventh joint pectinate, with four long spines in 
the first leg, in the second and third legs these becoming weaker. Claws strong in all. 
Last foui’ legs successively longer and relatively to their length more slender than the first three 
pairs, heavily armed with numerous brown-tipped spines. 
Pleon of five visible segments, dorsally strongly setose, first and second segments narrow and 
laterally covered by the seventh thoracic segment, the first being visible only dorsally; third segment 
posteriorly produced at the sides, covering the lateral portion of the fourth segment, which is the 
longest in the median line. This region is so setose that it is difficult to delimitate the segments. 
Telson triangular, with the tip rounded and armed with 6 spines, about two-thirds as long as 
broad; dorsal surface and posterior margin with numerous setre. Uropods extending somewhat beyond 
end of telson, inner branch the longer, not much longer than broad, rounded, with about 10 marginal 
