73 
c^ cirri kuije, never slender, usually stout, tajicring only very slightly, 
if at all, distally ; distal cirrus segments shorter than the proximal, 
broader than long, bearing prominent tubercles or spines dor- 
sally; opposing spine long and well developed; terminal claw 
stout, strongly curved (Maldive Islands and Ceylon to 
northern Australia, and northward to southern 
Japan) Amphimetra 
c- cirri small, very slender, nearly straight, tapering to a sharp 
point; distal cirrus segments proportionately as long as, or longer 
than, the proximal, more than twice as long as broad, with no • 
dorsal processes ; no opposing spine ; terminal claw long, very 
slender, and nearly straight (Arafura Sea; Moluccas) . . Homalometra 
Himerometra A. II. Clark. 
Key to the Species of the Genus Himerometra. 
a' Enlarged proximal pinnules slender, flagellate distally, and very long (slightly 
more than one half the length of the cirri), composed of from 36 to 40 
perfectly smooth segments most or all of which are longer than broad ; a 
few of the earlier segments are narrowly, but prominently, carinate; the 
earlier segments of the following pinnules are very strongly carinate; the 
segments in the outer half of the cirri have prominent dorsal spines 
b^ 20 to 25 arms; about 35 cirrus segments; all of the segments in 
the proximal pinnules are longer than broad (Persian Gulf) . . persica 
\y 35 to 61 arms; about 40 cirrus segments; a few of the basal segments 
in the proximal pinnules are broader than long (Philippine Islands) bartschi 
a" Enlarged proximal pinnules very stout, with all or nearly all of the com- 
ponent segments broader than long, or at least as broad as long ; none of 
the segments are carinate ; following pinnules without carinate processes 
on the earlier segments 
b^ enlarged proximal pinnules with about 30 segments, very stout basally 
and distally gradually tapering to a delicate and flagellate tip ; the 
distal edges of the segments in the middle half or proximal two-thirds 
are swollen and may be strongly everted, but are always smooth, 
never spinous 
c' cirri very stout, stouter than in any other species of the genus ; 
the enlarged proximal pinnules have the segments in the basal 
two-thirds with strongly produced and everted distal edges 
(Maldive Islands) sol 
c- cirri rather short and weak, without, or with only slight traces 
of, dorsal processes on the outer segments ; the enlarged proximal 
SIBOGA-KXPEDITIE XLII*. 'O 
