8 CRUSTACEA COPEPODA. It. 
Antennule (fig. 3 f) 17-jointed; eleventh to seventeenth joint together half as long again as the sum 
of the ten proximal joints; eleventh joint as long as, but much thicker than, the sixteenth very slender joint, 
and distinctly shorter than the very long fifteenth joint, while the fourteenth is short, as broad as long, the 
thirteenth somewhat longer and besides somewhat thick. — Maxillipeds (fig. 3 1) more slender than in the 
female and with a triangular protuberance on the distal joint of the proximal portion somewhat from its base. 
Length 0.85 mm. 
Remarks. — The female of A. tenerum differs from A. intermedium in having the cephalothorax 
rather oblong, the antenne, maxillule, maxille, and maxillipeds more elongated and slender, with the ter- 
minal spine or claw, or in the maxillule the terminal setee of the inner branch, conspicuously or even con- 
siderably longer than in that species, finally by the relative dimensions of the abdominal segments. The 
male is instantly separated from all other males hitherto described by the relative length of the joints in the 
antennule. 
Occurrence. — Gathered by the “Ingolf’’ at a single station. 
Davis Strait: Stat. 25: Lat. 63°30’ N., Long. 54°25’ W., 582 fathoms, temp. 3°3; 5 females, 3 males. 
6. Ascomyzon abyssi n. sp. 
(Pl. I, figs. 4 a—4 d.) 
Male. — A single mutilated specimen is to hand; it is allied and rather similar to the male of A. tene- 
vum, but differs in some particulars. Genital segment (fig. 4d) larger than in A. tenerum, as long as broad. 
Last segment nearly as long as broad, and somewhat longer than the two preceding segments together. 
Caudal rami slightly longer at the outer margin than broad, and much shorter than the terminal segment. 
Antennulee probably 17-jointed, but only 15 joints are preserved (fig. 4 a); eleventh joint somewhat 
longer than the next, but considerably shorter and thicker than in A. tenerum, conspicuously less than half 
as long again as broad, while in A. tenerum it is twice or more than twice as long as broad; fifteenth joint 
more than half as long again as eleventh and conspicuously longer than fourteenth and thirteenth joints 
together. — Antenne (fig. 4 b) with the terminal spine only as long as the penultimate joint. — Sipho (fig. 4 b) 
reaches only slightly beyond the insertion of the maxillipeds. — Maxillule (fig. 4 b) with the inner branch 
less elongated and broader than in A. tenerum, but its terminal setee half as long again as the branch; outer 
branch about one-third as long as the inner, but two of the terminal setee reach beyond its end. — Maxillee 
(fig. 4b) and mavxillipeds (fig. 4c) with the terminal claw less elongated than in A. tenerum. 
Length 0.88 mm. 
Remarks. — Instantly separated from the male of A, tenerum by the eleventh to fifteenth joint 
in the antennule, and by the abdominal segments. 
Occurrence. — Taken by the “Ingolf” at a single deep station. 
Davis Strait: Stat. 36: Lat. 61°50’ N., Long. 56°21’ W., 1435 fathoms, temp. 1°5; I male. 
