388 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



The body is more than twice as long as broad and only moderately 

 convex. The head is small and as seen from above is transversely 

 somewhat diamond-shaped with rounded angles. It presents in front 

 a slight prolongation between the antennulae, and on each side of the 

 short median i)rocess its outline is excavated above the bases of the 

 antennuljB. The posterior margin is curved, but near each end is a 

 faint indication of a lobe, projecting backward like the ocular lobes in 

 ^ga^ but the eyes are wanting. The antennulse arise near together on 

 each side of the front and are short, extending when reflexed but little 

 beyond the lateral margins of the head and only slightly surpassing the 

 fourth antennal segment. They are readily distinguishable into pe- 

 duncrdar and flagellar segments, the first three segments being of com- 

 paratively large size and about equal length ; the second segment much 

 flattened below against the antennae ; third more slender than the first 

 two and followed by a short, tapering six-jointed flagellum. The anten- 

 nulfe are in their natural position reflexed, the second segment being 

 articulated at an angle with the first. The antennae are considerably 

 longer than the antennulae and, when reflexed, slightly surpass the pos- 

 terior border of the third thoracic segment. They are inserted below 

 and a little outside of the antennulae. The first segment is short and 

 flattened below; the second is also short, the two together being hardly 

 longer than the basal antennular segment; the third segment is about 

 as long as the first two together, and the fourth is a little longer than 

 the third, but of slightly less diameter; the fifth is more than one-half 

 longer than the fourth, but is more slender and is followed by a slender, 

 tapering flagellum of about twenty-four segments. The last two pe- 

 duncular segments bear a row of elongate bristly hairs along the margin 

 which, when reflexed, is brought next the body, and the row is continued, 

 though with shorter hairs, along the flagellum. The palpus of the maxil- 

 lipeds is comj)osed of two segments of which the first is nearly square 

 and armed at the inner distal angle with a minute hook; the second 

 is bluntly triangular and armed at the apex, which is directed inward, 

 with three booklets. The external lamella is small and subcircular. 

 The outer maxillae are armed with short hooks at the tip ; the inner with 

 minute denticles. The mandibles are flattened and denticulate at the 

 tip and bear a three-jointed palpus of which the three segments decrease 

 in size to the last. 



The first thoracic segment is twice as long as the second; its anterior 

 margin is adapted to the head ; its posterior margin is nearly straight 

 above and rounded at the sides until the epimeral region is reached, 

 when a short, pointed projection juts backward, being the tip of the 

 epimerou on each side, here united with the segment. The next three 

 — second, third and fourth — thoracic segments are of about equal length, 

 and each a little over half the length of the first segment; their pos- 

 terior margins are nearly straight above and rounded at the sides; the 

 third segment is broadest. The fifth and sixth segments are each a 



