128 



THE VOYAGE OF H.M.S. CHALLENGER. 



produced, the second, third, and fourth abdominal segments lunate, but not very strongly 

 so ; first short, second, third, and fourth longer and nearly equal, fifth about half as long 

 again as the preceding, and sharply truncated ; caudal lamellae snbovate, nearly thrice as 

 long as broad, and equal in length to the last two abdominal segments, two short external 

 lateral setae and two longer ones on the apex. Anterior antennae (fig. 7) five-jointed, the 

 second joint as long as all the rest together ; setae numerous and short ; posterior 

 antennae (fig. 8) stout, the last two joints only about half as long as the second joint ; 

 "terminal claws short, branches of the fourth pair of feet equal. 



The male is in shape a long oval, about twice and a half as long as broad, and the 

 last two joints of the posterior antennae are long and slender, equalling in length the 

 second joint. 



Habitat. — South Atlantic, February 12, 1876 (Station 319); between Sydney and 

 Wellington ; off Zamboanga ; and in the North Atlantic, April 27, 1876. 



My description and drawing of the posterior antenna of the female differs altogether 

 as regards the length of the " finger " from that given by Dana ; but having verified it 

 by the dissection of two specimens, I am obliged to let it stand ; in all other respects 

 Dana's observation agrees with mine, and in the male I find the posterior antenna to be of 

 the slender type. Of course it is possible that I may be wrong in referring the female 

 specimens to Saphirina gemma, but their accurate agreement with the types, except in 

 this one particular, for the present at any rate, prevents my calling them by any other 

 name. From the spirit-specimens I cannot say what the original colour may have been, 

 except that some of the females are very opaque and dark-coloured, while Dana's were 

 colourless. The number observed was altogether very small. The spines of the swim- 

 ming feet (PI. XLV. fig. 18) are peculiar, being very short and broad at the base, and 

 strongly divaricate, while one side (especially in the case of the apical spines) merges into 

 a finely serrated basal convexity. 



9. Saphirina metallina, Dana (PI. L. figs. 11-17). 



Saphirina metallina, Dana, Crust. TJ. S. Expl. Exped. (1852), p. 1242, pi. lxxxvii. fig. 5. 



,, cylindrica, Lubbock, On some Oceanic Entomostraca collected by Capt. Toynbee, 

 Trans. Linn. Soc, vol. xxiii. p. 184, pi. xxix. figs. 13-15. 



Female. — Length, 1-1 lth of an inch (2*3 mm.). Cephalothorax elongated, the last 

 joint much narrower than the rest (one-third to one-fourth of the width) ; first segment 

 incompletely divided into two ; fourth produced behind into two broadly triangular 

 wings ; fifth as long as the preceding, but narrow and rounded at the angles ; abdomen 

 five-jointed, narrow, segments nearly equal in length ; first very narrow, with rounded 

 angles ; second, third, and fourth wider and strongly lunate ; fifth truncated, and very 

 finely ciliated on the posterior margin. Caudal lamellae quadrate, with nearly straight 



