204 
c' size large ; cirri usually more than XL ; Interradial perisomic plates 
usually inconspicuous or undeveloped (Faroe and Shetland Is- 
lands, Norway, western Sweden and Denmark, and northern 
Scotland, extending southward in deep water to the 
southern coasts of England and Ireland; absent from 
t h e N o r t h S e a) pc fastis 
c" size small; arms less than 60 mm. in length; cirri less than XXX\' 
d^ centrodorsal very low, evenly conv'ex, with very sloping sides; dorsal 
pole very small, from one third to one half of the diameter of the 
centrodorsal; arms 30 mm. to 40 mm. long (St. Thomas, Danish 
West Indies, .southward to Rio de Janeiro, Brazil) . dubcnii 
d' centrodorsal thin discoidal, the large flat dorsal pole being in width 
more than two thirds of the basal diameter of the centrodorsal ; 
arms usually about 60 mm. long (from Corsica and Sicily 
westward along the northern coast of Africa to Tan- 
gier, and southward to Senegal, including the Azores, 
M adeira, a ndtheCa nary Islands) nioroccafia 
Compsometra A. H. Clark. 
Key to the Species of the Genus Compsometra. 
a^ Cirri about one third of the arm length, exceedingly slender and delicate, almost 
hair-like, very slightly recurved, the earlier segments with greatly swollen arti- 
culations, those in the distal fourth gradually decreasing in diameter so that the 
cirrus ends in a sharp point; no opposing spine; arms 20 mm. to 40 mm. long; 
cirri X — XVII, 12 — 16, 7 mm. to 11 mm. long; Pj 3.5 mm. to 4 mm. long 
with 9 — II segments; P., 1.5 mm. long to 1.7 mm. long with 7 segments 
(Flo res to the Moluccas; o — 95 Metres) /oiigicirra 
a- Cirri short, not over one fifth of the arm length and usually less, stouter, in 
lateral view increasing in diameter in the distal half, with the outer segments 
much shorter than the elongrate earlier sesfments, never more than twice as lonsf 
as broad and usually much shorter; an opposing spine is always present 
b' cirri short, about one ninth of the arm length, composed of short segments 
of which the longest proximal (the fourth and fifth) are about half again as 
long as the median diameter and the last three preceding the penultimate 
are about as long as broad, or even broader than long; in the outer half 
the cirri are strongly recurved and the segments are strongly constricted 
laterally so that in lateral view this part of the cirri appears about twice as 
broad as the proximal; centrodorsal discoidal with a very broad bare dorsal 
pole nearly or quite 2 mm. in diameter; cirri XXXI\' — XXXM, 9 — 12, 
(usually 10), 7 mm. long; arms 60mm. to 65 mm. long (from Port Jackson, 
