245 
b' centrodorsal sharpl\- conical with straight sides, nearly or ([uit(_; as lonc^ 
as broad at the base Fariometra 
b'- centrodorsal less sharply conical, with rounded sides, or hemispherical, 
and lower 
c^ all the brachials have strongly produced and very spinous edges; 
P, very slender and delicate, markedly longer than P,,, with the 
outer segments very greatly elongated with overlapping and spinous 
distal ends (from southern Japan, the Hawaiian and 
P h i 1 i [^ p i n e Islands westward to C a j) e C o m o r i n , thence 
sou t h w es t w a rd to between Marion Island and the 
Crozets; from t li e Bay of Biscay northward to 54° 17' 
X. hit., and from Brazil northward to the Newfound- 
land banks; 248 — 2926 Metres). Trichometra 
c" the brachials do not have strongly produced and very spinous 
distal ends; at most the distal edges of the outer brachials are 
bordered with fine spines 
d^ Pj much elongated, between two and three times as long as P^, 
composed of 30 — 40 segments of which a few of the basal are 
short, the following becoming slender and greatly elongated 
(Arctic Ocean from western Greenland to the Kara 
Sea, and southward to Portugal and C h e s a [> e a k e 
Bay, and also in the vicinity of Marion Island, 
southeast of South Africa; 18 — 1800 Metres) . . . Hathrometra 
d- P, the same length as, longer than, or shorter than, P„; but if 
longer never more than slightly so, and with not more than 
20 segments 
e^ cirri with 20 — 30 relatively short segments of which the 
last six to thirteen are only very slightly, if at all, longer 
than broad 
P pinnules not especially long; distal pinnules the same length 
as the proximal pinnules; P„ resembling P^ and the following 
pinnules, slightly longer and stouter than Pj with somewhat 
fewer segments which are proportionately longer; Pj may 
bear a gonad, though these usuallv begin on P.; arms 
mm. 
to 60 mm. long; cirri L — LX, 21 — 30 (Kei 
^^ null. i\f vjw luiii. iwiix 
and Meangis Islands, and southern Celebes; 
204—1158 Metres) Nepiometra 
f- pinnules very long; distal pinnules not so long as the 
proximal pinnules; P, very slightly shorter than P, but 
similar to it, with about 18 elongated segments; following 
pinnules similar; arms about 20 mm. long; cirri about 
