POLYNOIDAE 97 



Genus Euphionella, gen.nov. 



As Euphione, Mcintosh, setisu Seidler (1924, p. 98), but characterized by the presence 

 of pseudo-elytra {vide Seidler, 1921, p. 90) and of completely smooth ventral bristles. 



The lateral tentacles are terminally inserted. There are 12 pairs of elytra arranged as 

 in Lepidoiiotm and completely covering the body. The segments having a dorsal cirrus 

 are provided with fan-shaped membranes which Seidler has called pseudo-elytra. 

 Ramose branchiae are present from the 3rd chaetiger on the hinder faces of the feet, and 

 small, globular branchial processes are found on the elytrophores and on the corre- 

 sponding structures in the cirrigerous segments. The dorsal bristles are exceedingly 

 fine barbed capillaries ; the ventral are stout, simple and without teeth or ornamentation 

 of any kind . 



Genotype: Physalidonotus lobulatus, Seidler. 



Euphionella patagonica, n.sp. (Fig. loa-l). 

 Occurrence. St. WS 212 (i). 



Description. The specimen measures 19mm. by 4 mm. without the feet for 25 

 chaetigers. In spirit there is no colour. The elytra are inserted on segments 2, 4, 5, 7, 

 9. . .21, 23, as in Lepidonotiis . The head (Fig. 10 a) is rectangular, rather longer than 

 broad. The lateral tentacles are terminal. A median groove is only slightly indicated. 

 I see two pairs of rather indistinct, almost contiguous, eyes at the outer and hinder 

 borders of the head. The lateral tentacles are about half as long again as the head and 

 the median tentacle is about three times as long as this. The tentacular cirri are inter- 

 mediate in length between the lateral and the median tentacles, the dorsal being slightly 

 longer than the ventral. The tentacular segment carries a few bristles. The ventral 

 cirrus of the ist chaetiger is slender and elongate, being about twice as long as the 

 foot. All these appendages are smooth, and have a slight subterminal dilatation. The 

 palps, on the other hand, which are about one-third as long again as the median tentacle, 

 are heavily papillated. 



The elytra (Fig. 10 b) are large, leathery, firmly attached and cover the whole body. 

 They are roughly slipper-shaped, and so disposed that the part corresponding to the 

 heel overlaps the part corresponding to the toe of the succeeding scale. The elytrophores 

 are narrowly oval structures with their long axis lying across the body. They are at- 

 tached to the elytra a little behind the middle point. The elytra are heavily fringed with 

 long cilia. In the first pair the fringe is absent only from the anterior border, and in the 

 remainder the fringe is confined to the outer and hinder edges. In addition to the 

 marginal fringe of cilia there are a number of shorter cylindrical papillae dotted about 

 on the scale itself in the neighbourhood of the marginal fringe. In the region of the 

 umbilicus the elytra show a transverse thickening or hillock caused by the increase of 

 connective tissue bet\\'een the two layers of cuticle, and on the top of this hillock or 

 crest there are three or four very large conical or capstan-shaped tubercles (Fig. 10 c). 

 Besides these there are two further kinds of tubercle. Between the crest and the hinder 



