12 
PACIFIC SCIENCE, Vol. II, January, 1948 
Fig. 2. Species of Arctonoe and Spinther. a-f, Arctonoe vittata (all figures are distal ends of notosetae and 
neurosetae from the first setigerous segment, X 425) : a, notoseta and b, neuroseta from station 71—40; c, noto- 
seta, and d, neuroseta from station 80-40; e, worn notoseta, and f, unworn notoseta from station L 4-41. 
g—j, Spinther alaskensis: g, neuropodial hook from a median segment, X 100; h, j, entire notopodial setae from a 
median segment showing variation in tips, X 425; i, bifid notopodial seta, X 812. 
may be free living. The present records are from 
known ranges in western and southern Alaska, 
in 5 to 150 fm., and from the Bering Sea in 
33 fm. 
Genus Lepidonotus Leach 
are none on the present individuals or on those 
of the original collection ( loc. tit.). 
L. rohustus was first described from Shelikof 
Strait, Alaska, in 48-65 fm. The present records 
are from Canoe Bay and Cold or Pavlof Bay, in 
15 to 40 fm., not far from the type locality. 
Lepidonotus robustus Moore 
Lepidonotus rohustus Moore, 1905^: 544-546, 
pi. 36, fig. 32-35. 
Collections. Stations 51-40 (3); 61-50 (1); 
Canoe or Pavlof Bay (1). 
These individuals agree closely with Moore’s 
description (1905: 544). It now seems doubt¬ 
ful that this species is actually the same as 
L. helotypus (Grube) (1877: 49) originally 
described from China, although earlier I (1938c: 
109) followed Seidler (1924: 56) in referring 
it to the latter. L. helotypus is said to have 
small, dark, nailheaded spines on elytra. There 
Genus Halosydna Kinberg 
Halosydna brevisetosa Kinberg 
Halosydna brevisetosa Kinberg, 1857: 18, pi. 5, 
fig. 25; Berkeley, 1942: 189. 
Polynoe brevisetosa Johnson, 1897: 167-170, 
pi. 6, fig. 24, pi. 7, fig. 31, 40, pi. 8, fig. 46. 
Collections. Station 51-40 (1). 
This well-known species is common through¬ 
out the northeast Pacific, from Alaska south to 
southern California. It is sometimes commensal, 
in tubes of other chaetopods, where it attains 
comparatively great size. The present record is 
from Canoe Bay in 25 to 40 fm. 
