The 18th and 19th segments are articulated 

 by a "knee joint." 



The antenna, the mouth parts, and the first 

 to fourth pairs of legs are similar to those of 

 the female. 



The fifth pair of legs (plate 10, figs. 4-6) 

 is asymmetrical — the right exopod is modified 

 into a grasping organ in the form of a power- 

 ful chela. The left e.xopod is 2-segmented; the 

 distal segment has two strong, curved spines, 

 the distal parts of which are densely pitted. 



Remarks 



This species was established by Giesbrecht 

 (1895) upon a single male specimen from the 

 northeastern Pacific. As the species does not 

 appear in any other lists, the present speci- 

 mens constitute the first record since the orig- 

 inal discovery. The female is described here 

 for the first time. Sixteen female specimens 

 have been deposited in the U.S. National Mu- 

 seum (USNM 113375, 113376). 



FAMILY LUCICUTIIDAE 



Lucicutia flavicornis (Claus, 1863) 

 (Plate 10, figs. 7-13) 



2 adult females, 1.41 to 1.43 mm. 

 12 adult females, 1.38 to 1.94 mm. ; 

 6 adult males, 1.45 to 1.48 mm. 

 1 adult male, 1.51 mm. 



3 adult females, 1.65 to 1.94 mm. 

 1 adult female, 2.04 mm. 



1 adult male, 1.66 mm. 



Remarks 



The female of this species can be distin- 

 guished by the elliptical prosome and the shape 

 of the fifth pair of legs (fig. 7). The female 

 from station 16 had an abnormal left fifth leg 

 — 2 teeth were present proximal to the external 

 spine of the .second exopodal segment (fig. 8) . 



The body of the male (fig. 9) is shaped like 

 that of the female. The left antennule is 21- 

 segmented and slightly modified for grasping 

 the female. The basis of the left fifth leg (fig. 

 10) has internally a large projection pointed 

 di.stally. The internal edge of this projection 

 has 5 or 6 teeth. In the right fifth leg, both 

 the exopod and the endopod are 2-segmented. 



The proximal exopodal segment is slightly 

 curved inward and lacks processes on the in- 

 ternal margin. 



Four male specimens abnormal in the shape 

 of the fifth pair of legs were from stations 5 

 and 7. The general shape of the body of these 

 males (fig. 11) does not differ from that of 

 the normal male, but the fifth pair of legs 

 (figs. 12 and 13) differs in the following as- 

 pects: The projection on the internal margin 

 of the basis in the left leg is tapered distally, 

 with 3 to 4 acute teeth along the internal edge. 

 The first exopodal segment of the right leg has 

 proximally a triangular process along the in- 

 ternal margin. The second exopodal segment of 

 the same leg is pronouncedly curved. 



FAMILY HETERORHABDIDAE 



Heterorhabdus papilliger (Claus, 1863) 

 (Plate 10, figs. 14-21) 



Occurrence 

 Sta. 5. 



Sta. 7. 



Sta. 9. 



Sta. 13. 



Sta. 15. 



Sta. 16. 



Remarks 



15 adult females, 1.88 to 2.24 mm. ; 



14 adult males, 1.98 to 2.07 mm. 



15 adult females, 1.91 to 2.31 mm. ; 

 6 adult males, 1.94 to 2.14 mm. 



4 adult females, 2.17 to 2.21 mm.; 

 2 adult males, 2.14 to 2.17 mm. 

 4 adult females, 2.41 to 2.54 mm.; 

 12 adult males, 2.27 to 2.65 mm. 

 11 adult females, 2.40 to 2.62 mm. ; 

 4 adult males, 2.55 to 2.62 mm. 

 18 adult females, 2.48 to 2.58 mm. ; 

 10 adult males, 2.48 to 2.55 mm. 



This species is one of the most common in 

 the present collections. It can be identified 

 readily by the triangularly produced forehead 

 in lateral aspect (figs. 16 and 20) and the 3 

 equal terminal spines of the maxilla (fig. 18). 

 In the fifth leg of the female (fig. 19), the sec- 

 ond exopodal segment has internally a long, 

 curved spine, which is longer than the third 

 exopodal segment. The fifth pair of legs (fig. 

 21) of the male has a beaklike projection on 

 the internal margin of the second right exopo- 

 dal segment. 



560 



U.S. FISH AND WILDLIFE SERVICE 



