294 THE SCHIZOPODA. 
surface with setae of the two distal joints of second pair in the main as in fully 
developed specimens; third pair of legs almost rudimentary; branchiae rudi- 
mentary. 
The three anterior pairs of pleopods with the endopod very small though 
terminating in a seta and the exopods well developed; the two posterior pairs 
are smaller, with the exopod setiferous while the endopod is rudimentary, with- 
out any seta.— Telson more slender than in the preceding stage; its terminal 
part between the inner postero-lateral spines considerably produced, the terminal 
margin transverse but shorter and with only five spines proportionately smaller 
than in the preceding stage; the inner pair of postero-lateral spines with the 
proximal half a little broader than in the preceding stage and considerably broader 
than the intermediate pair, which are more slender than in preceding stage. 
Length of the specimen described 3 mm.— It was taken at Sta. 4588, 
October 12, 1904, Surface. ‘ 
Remarks.— The shape and setae of the two distal joints of the second 
elongate pair of legs prove beyond doubt that the last-named specimen belongs 
to Stylocheiron carinatum G. O. 8. And a comparison between this specimen 
and the specimen in the intermediate Furcilia-stage gives the result, that both 
belong to the same species. And as nothing was known on the larval stages 
of any species of the aberrant genus Stylocheiron I find it useful to give here what 
I can, though the younger specimen is not well preserved. The larvae of S. 
carinatum differ from those of Nyctiphanes, Thysanopoda, Euphausia, Pseud- 
euphausia, and Nematoscelis by having no denticle on the lower margin of 
the carapace; I think that this feature affords a good generic character; yet 
it may be very possible that the hitherto unknown larvae of the genus Nemato- 
brachion agree with Stylocheiron in possessing no marginal denticles. The 
larvae of Stylocheiron agree, as might be expected, with those of Nematoscelis 
(and probably of Thysanoéssa) in having the two distal peduncular joints of 
the antennulae more slender than in those of the other genera mentioned, but 
they differ from the larvae of Nematoscelis by the shape of the frontal plate 
and by having the dorsal keel of the carapace smaller and remarkably far behind 
the middle. But judging from the two above-described larval stages of S. 
carinatum the development and structure of the larvae of the genus Stylocheiron 
seems to deviate but little from other genera of the order. 
