47 



Stat. 260. December 16 and 18. 2,3 miles N. 63° W. froni the north point of Nuhu Jaan, 

 Kei-island. 1 specimen. 



The two specimens from these stations are adult females, but unfortunately not well 

 preserved. They differ from the typical specimens of H. pulchra in the following particulars. 

 The bod)- is more robust ; the eyes are conspicuously darker; the telson is shaped quite as in 

 the female of the following species, not constricted at some distance from the base, but tapering 

 slowly and regularly from near the base to the broad end, with 3 or 4 spines on the basal part 

 and with 3 pairs of long terminal spines as in H. parva. In other characters these specimens 

 agree with the typical H. pulchra, and judging from the variation in the shape and armature of 

 the telson in the following species I suppose that the differences mentioned are not of specific value. 



26. Hemisiriella parva n. sp. PI. VI, figs. ia — 2e. 



Stat. 96. June 27. South-east side of Pearl-bank. Sulu-Archipelago. 15 m. Plankton. 1 specimen 



(adult 0). 

 Stat. 132. July 25. Lat. 5 56'./ N., long. I2Ó°25'E. 3302 m. Plankton, surface. 1 specimen. 

 Stat. 148. August 10. Lat. o°i7'.6S., long. 129 14.5 E.- 1855 m. HENSEN vertical net, from 



1000 m. depth to surface. 1 specimen. 

 Stat. 203. September 19. Lat. 3°32'-5 S., long. I24°I5'.5 E. 4892 m. HENSEN vertical net, 



from 1500 m. depth to surface. 2 specimens (cf and 9> both adult). 



Description. — Slender. Frontal plate rather feebly produced, with the tip rounded. 

 Eyes smaller than in H. pulchra, red. Antennal squama in the female (fig. 2 0) scarcely two 

 and a half times as long as broad, in the male (fig. 2 a) slightly longer and narrower ; terminal 

 lobe much broader than long. Uropods (fig. 2 c) more narrow than in H. pulchra, subsimilar in 

 both sexes; the exopod conspicuously shorter than the endopod, with 3 — 6 marginal spines, and 

 its distal joint somewhat more than twice as long as broad. The telson reaches the articulation 

 of the exopod and its scarcely two and a half times as long as broad. In the two adult females 

 it (figs. 2c and 2a 1 ) tapers gradually but slowly from near the base to the rather broad end; the 

 proximal part has 2 or 3 small spines on each margin, the distal part 6 — 8 pairs of irregularly 

 arranged spines, all short excepting the last pair which is somewhat longer; the end has 3 small 

 spines and 3 pairs of long spines, the second pair considerably longer than the inner pair. In 

 the single male from the "Siboga" the telson (fig. 2 e) is intermediate as to shape and spinulation 

 between that in the female and the telson in the typical H. pulchra : it is somewhat constricted 

 before the middle, the basal part being widened with two pairs of spines, the distal pair of 

 which are thick; the distal half of the telson tapers more than in the female, so that its end 

 is considerably more narrow ; the lateral spines of this part are much longer and thicker than 

 in the female, and the distal four pairs increase posteriorly gradually and strongly in length ; 

 the end has only 2 pairs of long spines, the inner of which are not longer than the last lateral 

 pair, while the outer pair are twice as long ; of intermediate small spines only 2 are present, 

 and they are extremely small. (The two usual, long, terminal seta? are wanting, but they may 

 be lost in my specimens). 



Length of the adult male 6.5 mm.; an adult female measures 6.2 mm., the other adult 

 female only 5.3 mm. 



