. Discovery reports. Discovery (Ship); Scientific expeditions. IS8 DISCOVERY REPORTS 2mm and about the last 20 chaetigers are free from eggs. The prostomium is bluntly conical and without eyes. The buccal and the two (.'') following segments are long, achaetous and indistinctly separated. As in Hetero- cirrus (see Fauvel, 1927, p. 96), on the last achaetous segment or on the anterior border of the ist chaetiger there is a pair of gills and a pair of coiled palps (Fig. 62) which are about equal in length to the first ten chaetigers. The gills are for the most part lost, but it can be seen that
. Discovery reports. Discovery (Ship); Scientific expeditions. IS8 DISCOVERY REPORTS 2mm and about the last 20 chaetigers are free from eggs. The prostomium is bluntly conical and without eyes. The buccal and the two (.'') following segments are long, achaetous and indistinctly separated. As in Hetero- cirrus (see Fauvel, 1927, p. 96), on the last achaetous segment or on the anterior border of the ist chaetiger there is a pair of gills and a pair of coiled palps (Fig. 62) which are about equal in length to the first ten chaetigers. The gills are for the most part lost, but it can be seen that they are con- tinued for at least the anterior two-thirds of the body. They are very long, a gill from the middle of the body being equal in length to about 15 chaetigers in the middle. ^0 Fig. 62. Tharyx cpiloca. Anterior end. (Position of the gills indicated by the broken lines.) of the body. After the 30th chaetiger the body is no longer swollen with eggs, and the segments are half the length of those in the sexual region. The bristles consist of very long fine capillary chaetae, in length about equal to twice the breadth of the body. There are no hooks. The pygidium is conical and the anus terminal. Remarks. The position of the first gill and palp would seem to refer this form to Heterocirriis, Grube; on the other hand, the absence of crochets in the feet is charac- teristic of Tharyx. This species is very close to, and possibly identical with, Hetero- cirriis dndnnatus, Ehlers (1908, p. 129) from 48° 57' S, 70° W. The differences are these: Ehlers' type specimen measured 18 mm. by 1-5 mm. for no segments; Ehlers states that towards the posterior end of the body the segments are longer than in the middle; Ehlers describes a pair of gills only on the last achaetous segment and places the palps on the ist chaetiger. My specimen measures 27 mm. by 3 mm. for 50 chaetigers; towards the posterior end the segments are much shorter than in the middle of the body and both ist gill
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectscientificexpedition
