58 

 3- Gastrosaccus parvus n. sp. PI. VIII, figs. 3« — ^n. 



Stat. 37. March 3031. Sailus ketjil, Paternoster-islands. 27 m. and less. Plankton, surface. 



I specimen. 

 Stat. 315. February 17/18. Anchorage East of Sailus Besar, Paternoster-islands. Depth up to 



36 m. Plankton, i specimen. 



Description. — This species, of which two adult males are to hand, is so closely 

 allied to G. indiciis, that it may be sufficient to point out the differences. It is somewhat smaller 

 than G. mdicus. The frontal plate is considerably longer (fig. 3^'), triangular, somewhat broader 

 than long, with the end subacute. Eyes a little larger than in G. indiais, otherwise as in this 

 species. Antennal squama scarcely reaching beyond the end of the second, long joint of the 

 endopod (fig. 3/'). The male pleopods more slender than in G. indiats and differing in many 

 particulars. First pair (fig. 3^) with the endopod proportionately still somewhat smaller than in 

 G. indictis. Second pair (figs. 2,d — 3^) with the exopod a little longer than in G. indiciis, the 

 basal joint very long, twice as long as the rest which consists of four joints, each of which with 

 a conspicuous, stiff seta; the endopod is much longer than in G. indiciis, two-thirds as long 

 as the exopod, consisting of six joints, the proximal one a little shorter than the sum of the 

 others, with its proximal three-fifths gradually expanded on the outer side and this triangular 

 expansion terminating in a very long and strong seta. Third pair of pleopods (fig. 3/") reaching 

 nearly to the end of the telson; its exopod with the basal part normal, simple, and its end 

 terminating in two minute processes (fig. 32) while setae seem to be wanting; if the endopod 

 exists, it must be the narrow lobe marked off from the peduncle and lying close to the base of 

 the exopod (figs. 3^'' — 3//). Fourth and fifth pairs (figs. 3/' and 3;;/) as short as in G. indiciis^ 

 but differing strongly in having the exopod quite rudimentary, consisting of an extremely minute 

 joint terminating in a seta (fig. 3 /) ; the endopod is unjointed, its broad end a little incised, 

 with a few, strong setae, two of which are curved. The exopod of the uropods with 10 spines; 

 the endopod with 4 spines along the inner margin. Telson (fig. 3 ;/) a little shorter than in 

 G. indiciis, being slightly more than two and a half times as long as broad ; each lateral margin 

 with 8 spines, the terminal spine very long, the penultimate still longer, three times as long 

 as the penultimate pair. 



Length of an adult male 5.4 mm. 



Gastrosaccus bengalcnsts n. sp. 



Of this new species a good number of specimens are to hand; they have been taken pelagically in the Bay of Bengal by the 

 Danish "Galathea" Expedition, Dec. 20, 1S45. It is closely allied to G. iiidkus m. and G. (Haplostylus) ei-ythrccus Kossm., but differs 

 from both in several particulars, especially in the male pleopods. Frontal plate a little more produced than in G. indiciis, but scarcely as 

 long as in G. parvus. Eye-stalks distinctly broader than the eyes. Antennal squama about as in G. indiciis. The pleopods of the male 

 afford the best characters. The first pair have the endopod longer than in G. indiciis, somewhat less than half as long as the exopod and 

 somewhat narrow ; the exopod with six joints, the proximal one as long as the sum of second to fourth. In the second pair the exopod 

 consists of nine joints, the first joint about as long as the sum of the other joints, the penultimate joint with a very strong, the preceding 

 joint with a strong seta, the latter joint besides with a small, obtuse spine, while an acute spine is found on the antepenultimate joint j 

 the endopod consists of six joints, the first of which as long as the sum of the others and broad to near the. middle where a strong seta 

 originates, then suddenly narrower and distally slender: the other joints slender: second joint with a nearly spiniform. curved seta, the 

 four distal joints naked, the sixth joint ending in a fine seta. Third pair of pleopods have the endopod rudimentary, viz. a small, oblong 

 joint marked off from the peduncle; the exopod reaches about the middle of the telson, it has proximally 2 or 3 fine spines and terminates 

 in a minute, nearly claw-like process, before the base of which a minute seta is seen; finally its penultimate joint is distally a little widened 



