THALESTRIS. 125 



3. THALESTKIS RTJFOCINCTA, Norman (M.S.). PI. LVII, 



figs. 1_9. 



Body elongated, slender ; rostrum very long, curved 

 and sharp ; anterior antennae 9- jointed, the first joint 

 nearly as long as the following three ; inner branch of 

 the posterior antenna 2-jointed. Mouth organs large 

 and well developed; second foot- jaw (fig. 4) very similar 

 to those of the two preceding species ; first joint 

 setose on the outer margin ; inner margin of the hand 

 finely ciliated, nearly straight, and bearing a short 

 seta over the middle ; outer margin angulated and also 

 provided with a short median seta ; terminal claw 

 long, slender, and having three slender setae attached 

 near the base. First pair of feet (fig. 5) stronger and 

 more powerfully clawed than in T. mysis, but other- 

 wise very similar ; inner branch of the second pair in 

 the male (fig. 6) indistinctly 3-jointed, the last two 

 joints being imperfectly separated; apex armed with 

 one short crooked spine and two short setae; the 

 spines of the outer branch in all the swimming-feet 

 have strongly aculeate margins (fig. 6 a a). Inner 

 segment of the basal joint of the fifth foot in the 

 female (fig. 7) elongated, subtriangular, bearing five 

 setae on the inner margin ; second joint ovate ; distal 

 half of the outer margin four times indented and bear- 

 ing six setae of unequal lengths ; the margins of both 

 joints densely ciliated; in the male (fig. 8) the basal 

 joint is broad, its inner segment convex, but only 



