iQo DISCOVERY REPORTS 



Remarks. I have compared these examples with some specimens from Spitzbergen 

 and except in the matter of size I can find no significant differences. I believe this to be 

 the first record of this species from southern tropical w^aters. 



Genus Euchone, Malmgren 



Branchiae symmetrical, not spiral, vv^ithout eyes or dorsal processes. A high palmar 

 membrane. Cirriform intrabranchial filaments present. A collar is present and otocysts. 

 At the hinder end there is a large anal depression in the form of a ventral gutter or 

 spout. The first chaetiger carries bordered capillary bristles. The bristles of the re- 

 maining thoracic chaetigers consist of bordered capillaries and usually also of spatulate 

 or subspatulate chaetae. The thoracic hooks have long downwardly directed manubria. 

 There are no pickaxe bristles. The abdominal hooks have short bases without a posterior 

 prolongation, and the abdominal bristles are narrow capillaries. 



Euchone pallida, Ehlers. 



Ehlers, 1908, p. 159, pi. xxi, figs. 10-15; P'- ^^''' ^g^. 1-4. 

 Benham, 1927, p. 139, pi. iv, figs. 126-130. 

 Monro, 1930, p. 203. 



Occurrence. St. 123 (7); 366 (4). 



Specific characters. The only complete specimen, from St. 366, is slender for the 

 species and has a body-length of 45 mm. and a gill-length of about 15 mm. It has 32 

 abdominal chaetigers. The specimens from St. 123 are smaller and have an average 

 body-length of 20 mm. with 22 abdominal chaetigers. They have all lost their gills. 

 In most of the known examples of this species the length of the gills is more than half 

 that of the body. The palmar membrane extends about two-thirds of the distance up 

 the gills. Branchial barbules very long and slender. Tentacular filaments without 

 barbules are present inside the branchial plume. 



The collar is open in the mid-dorsal line, at the sides of which it joins a pair of longi- 

 tudinal fleshy pads below the branchiae. Benham calls these the nuchal gland. The 

 collar is of an equal height all the way round except where it slopes down to join the 

 nuchal gland. It is deeply incised in the mid-ventral line. The thoracic bristles are all 

 narrowly- winged capillaries. There are no spatulate or subspatulate bristles. The thoracic 

 uncini have long downwardly-directed manubria and denticulated heads. There are 

 eight chaetigers in the thorax. The abdominal uncini have a short base with no back- 

 ward process, about four rows of denticles above the main fang and a pointed boss 

 below it. The abdominal bristles are slender, narrowly-bordered capillaries. The caudal 

 membranes are deep and extend for the last 10-12 segments. 



Remarks. The characteristic feature of this species is the absence of spatulate or 

 subspatulate bristles from the dorsal bundles of the thorax. Augener (1932 rt, p. 70) 

 makes this species a synonym of Euchone analis, Kroyer. With this opinion I disagree. 

 Kroyer's species has spatulate or subspatulate bristles in the thoracic notopods, which 

 are wholly absent in the present species. 



