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DISCOVERY REPORTS 



Isometra flavescens n.sp. (Plate V, figs. 3 and 4) 



St. 160. 7.11.27. Near Shag Rocks. 53° 43' 40" S, 40° 57' W. 177 m. Gear DLH. Bottom: 

 grey mud, stones and rock. Six males and six females. 



Description. This species is fairly small but robust. The arms of all twelve specimens 

 are broken at the tips. They appear to have been just over 40 mm. long when complete. 

 The specimens are described as having been "mustard-yellow" in colour when alive, 



Fig. 16. Isometra flavescens. a, cirrus, b, distal brachials, c, proximal brachials and Pj, Pj and P3. 

 d, a middle genital pinnule of a female, e, a middle genital pinnule of a male. /, ambulacral skeleton of a 

 distal pinnule, a-c, xii. d, e, x 13. /, x 66. 



and they are still a strong yellow in spirit. In four of the males the yellow colour is 

 overlaid by a dusky shading on the pinnulars, or on the pinnulars and brachials, giving 

 them a dark appearance. The basal segments of the cirri are deep yellow while the distal 

 appear in contrast a pure white. 



The centrodorsal is conical, closely beset with cirrus sockets which may entirely 

 cover it or leave free a small flattened dorsal pole. The sockets are arranged in rows 

 which are regular near the apex but less so near the periphery. The ventral edge of the 

 centrodorsal is slightly produced at the interradial corners. 



