420 



REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



[76] 



Tlie gnathopods and ])er;ropods are essentially as in S. robustus^ ex- 

 cept that the fourth and fifth perieopods are much narrower and very 

 nearly as in S. aretieus. 



The pleon is broad anteriorlj', but strongly com])resaed posteriorly, 

 and the dorsum rounded. The sixth somite is shorter than the antennal 

 scale, more than half as high as long, and very strongly comi)ressed. 

 The telson is about as long as the sixth somite, sulcated as in S. robnstus, 

 and rather obtusely triangular at the tip, which, however, is mucronate. 

 The inner lamella of the uropod is about four times as long as broad 

 and regularly lanceolate in outline, without any angular expansion near 

 the middle of the outer edge. Tlie outer lamella is nearly a third longer 

 than the inner, about four and a half times as long as broad, and the 

 outer margin terminates in a tooth about two-ninths of the length, or 

 the width of the lamella, from the tip. 



The peculiar sexual appendages (petasma) of the first pair of x^leopods 

 are very nearlj" as described and figured for S. rohnstus, although there 

 is a little difference in the form and proportions of the hook-bearing 

 j)rocesses and unarmed stylets of the main branch of each appendage : 

 the lateral unarmed stylet (marked c in the figure of S. rohnstus) is 

 stouter than in that species and truncated at the tip, while the mesial 

 stylet [d) is nearly as long as the hook-bearing process {g) with which 

 it is connected at base. 



The females are considerably larger and stouter than the males, the 

 peduncles of the antennulae are apparently a little shorter, and the eyes 

 slight!}' smaller. 



Although a considerable number of specimens have been taken by 

 the Albatross, none of them are perfect and most of them are in very 

 bad condition. 



The branchiae are all much smaller than in 8. robustns, the posterior 

 pleurobrauchia of the twelfth (antepenultimate) somite is replaced by 

 a simi^le lamella like that upon the somite next in front, and the two 

 branchifB of the penultimate somite are very small, as in S. aretieus. 



Three specimens (710C) from Station 2051 give the following measure- 

 ments, of which some, on account of the imperfections and soft condi- 

 tion of the specimens, are only approximate : 



Sex 



Lenjtth from tip of rostrum to tip of telson 



Lenfith of carapax along <lor8um 



Leutrtli of oyo-stalk and eye 



Gruatcat (liamotcr of oyo 



LoDKtli of jjcduDclo of antennula 



Lenu'tli of Its distal se^nnent 



Lenjitli of antennal scalo 



Breadth of antennal scale 



Length of sixth somite of ploon 



Hii;lit of sixtli somite of pleon 



Lonctli of telson 



Lcujtth of inner lamella of nrojjod 



Breadth of inner lamella of iiropod 



Lengt h of outer lamella of uropod 



Breadth of outer lamella of uropod 



50 



18 

 2.9 

 1.0 

 0.8 

 2.6 

 8.2 

 2.8 

 8.0 

 4.2 

 8.1 

 8.0 

 2.0 



10.8 

 2.4 



57 



21 

 3.0 

 0.9 



10.0 

 2.C 

 8.8 

 3.3 

 9.0 

 4.8 

 8.0 



72 



26 

 3.0 

 1.1 



13.0 

 3.2 



10.8 

 5.8 

 10.0 



