92 Papers from the Department of Marine Biology. 
of such an association in this latter case. As we do not know whether 
the original species is a commensal of crinoids, and in view of certain 
morphological discrepancies, I describe the Torres Straits form as a 
new variety. 
The two cotypes of P. minuta were incomplete individuals and on 
this account the generic ascription was queried. In the series under 
consideration there are three complete individuals, each having 15 pairs 
of elytra. There is no reason why this species should not be definitely 
assigned to the genus Polynoé, though there is good reason for under- 
taking a revision of this and kindred genera. 
The characters which separate the Torres Straits form from the 
original species are as follows: 
(1) The head is provided with two pairs of very distinct eyes, the one placed 
laterally near the posterior angle, the other on the posterior border. The head 
is covered with dark pigment, but there is a pigment-free ring round the pos- 
terior eyes (the depression separating the two lobes of the head is free also). 
In the Maldivian individuals there were no signs of eyes. 
(2) The lateral tentacles have a much swollen base—in the type species 
they are thin throughout. The lateral anterior angles are rounded instead of 
slightly pointed. The palps are rather longer in proportion to the size of the 
animal. 
There are a number of additional points, some of which could not be 
mentioned in the original account, which are treated below: 
Colouration: The dorsum, with the exception of 2 longitudinal pigment-free 
bands, is covered by dark brown pigment, not soluble in 70 per cent alcohol. 
The markings are hidden by the elytra, which are uniformly pigmented. 
Shape: In smaller specimens tapering rather abruptly, in a larger one of 
uniform breadth up to end. 
Number of elytra: Fifteen. They cover almost the entire dorsum. 
Sete of neuropodium: These fall into the following categories: (1) Very 
long and slender, long drawn-out head slightly enlarged, ending in a blunt 
apex with a projecting tooth of almost equal size underneath (type B). 
(2) Thicker, head more pronounced, sharp incurved apex with prominent 
tooth underneath; one or two of the dorsalmost often have prominent spines 
on the convex surface of the head (C). Ventrally, however, spines are never 
present (D) and they pass into (3) a still stouter type with shorter head, apex 
still more incurved, tooth not so prominent (and in the ventralmost altogether 
absent (E)). 
This succession of setz is almost identical with that in P. minuta, as I find 
on comparison with the type specimens, which I did not describe with sufficient 
fulness in 1910. Sete of type 1 occur there, though they were not mentioned 
or described; the other types were given, and the only difference is the absence 
of setze with a very definite row of spines in P. minuta. 
Measurements: Those of three complete individuals are given: 
Breadth, 
Specimen. | Length including No. of 
= ay ee : segments. 
parapodia. 
mm mm. 
y: ieee 10 2 50 
BB Gomori 8 De 39 
OR nate 6 ets 33 
