POLYCILETA-BENHAM. 33 



Station 2, 318 fathoms (five). 

 Station 3, 157 fathoms (three). 

 Station 8, 120 fathoms (ten). 

 Station 10, 325 fathoms (two). 

 Station 12, 110 fathoms (four). 



Distribution. South Victoria Land, Bouvet Island, Kaiser Wilhelm II Land, 

 (Ehlers), Graham's Land, Alexander Land (Gravier). 



Genus HOLOLEPIDELLA Willey. 



HOLOLEPIDELLA FLYNNI sp. nov. 



(Plate 5, figs. 14-20). 



The species is founded on four slender worms collected off Maria Island, lasmania, 

 by Professor T. T. Flynn. The pale grey dorsum is covered by white and nearly 

 opaque elytra, which occur almost over the entire length of the body. 



The largest individual is about 40 mm. in length and contains 63 segments. 

 Its greatest breadth is in the region of segments 5-13, where it measures 4 mm. over 

 the body; 5-5 mm. across the parapods ; and 7-5 mm. including the chaetae. From 

 this point the body begins to taper so that at the 26th segment the breadth is only 

 2-5 mm., while at the 40th it is but 2 mm. The length of the parapods does not sensibly 

 decrease till quite close to the hinder end. 



The total number of elytra is rather difficult to decide, as the majority have 

 fallen away; but by counting the elytrophores I find that there are at least 26 pairs. 

 In a small individual, which measures 27 mm., with 61 segments, 18 pairs of elytra 

 are in position, the last being on segment 41, but there are elytrophores posterior 

 to this. 



I find, as did Willey, that it is by no means easy to distinguish elytrophores 

 from cirrophores, from which the cirri have fallen away, both are nearly in the same 

 line, close to the margin of the body; but by comparing the four specimens and 

 especially after the examination of one that was stained and mounted, which 

 lacks, however, the last 2-3 segments, one can fairly readily distinguish the two, 

 structures. 



In this species the elytra are arranged as follows : The first 12 are ou the usual 

 segments, that is (counting the peristomium as 1st) on the segments 2, 4, 5, 7-21, 23; 

 the next six elytra appear to be regularly on every third segment 26, 29, 32, 35, 38, 41. 

 It is hereafter that irregularity creeps in, but in all the four individuals I find 

 elytra or elytrophores on the next segment, 42nd ; in two instances they occur on 

 the next two segments, that is, on three consecutive segments. Further back they 

 are either on alternate segments or with gaps of two or three segments at intervals; 

 or on consecutive segments. The arrangement is not symmetrical, so that no general 

 statement covers their position ; no formula can be given for these posterior elytra, 



83892 E 



