178 DISCOVERY REPORTS 



The thorax is thick and arched dorsally. There are no eye-spots. There are large 

 lateral flaps on the second and third segments and a small one on the fourth. There are 

 II ventral gland shields. Each of the three pairs of gills consists of a pair of stout and 

 richly branched trunks. The nephridia extend from the third to the twelfth segments. 

 There are 17 thoracic notopods. The dorsal bristles have distinct borders and a long 

 denticulated apex. The double rows of hooks extend from the seventh to the sixteenth 

 uncinigers. The hooks have about six rows of teeth above the main fang. Posteriorly 

 the abdominal tori are gradually transformed into narrow pinnules. 



Remarks. I suspect that Amphitrite voriabiUs, Risso of Ehlers (1901, p. 208), from 

 Puerto Condor belongs here. 



Genus Leaena, Malmgren 

 No gills. The anterior segments are usually furnished with lateral lobes. The notopods 

 begin on the fourth segment and the neuropods on the fifth. The dorsal bristles are 

 smooth and widely bordered. The hooks are in two rows from about the eleventh to the 

 twentieth segment. 



lo-i I thoracic chaetigers L. abranchiata, var. antarctica 



17 thoracic chaetigers ... ... ••■ •■• ••• •■• ••• ••• ••• L. collaris 



Leaena abranchiata, Malmgren, var. antarctica, Mcintosh. 



Hessle, 191 7, p. 197. 



Benham, 1927, p. 106. 



Leaefia antarctica, Mcintosh, 1885, p. 462, pi. xlviii, figs. 9 and 10; pi. xxviiiA, figs. 10 and 11. 



Occurrence. St. 45 (i). 



Specific characters. A single, damaged, immature specimen measuring about 

 10 mm. by i mm. No eye-spots. Lateral lobes on the second, third and fourth seg- 

 ments. Those on the fourth segment very little developed. The third segment has a low 

 and inconspicuous collar on the dorsal surface. There are 10- 11 thoracic chaetigers and 

 about 10 ventral gland shields. The bristles have broad wings and long and fine tips. 

 Above the main fang of the hooks there is a row of teeth surmounted by about three 

 rows of denticles. 



Leaena collaris, Hessle. 



Hessle, 1917, p. 198, pi. ii, figs. 9, 10, text-fig. 52 a-c. 

 Monro, 1930, p. 188. 



Occurrence. St. 123 (i); MS 15 (3). 



Specific characters. One specimen from St. MS 15 is very large and measures 

 about 70 mm. by 4 mm. at the widest part for 55 chaetigers. There are no eye-spots. 

 Lateral lobes present on the second, third and fourth segments. The third segment has 

 a well-developed lobed or crenate collar on the dorsal surface. There are 17 thoracic 

 chaetigers and 1 1 ventral gland shields. The bristles have wide wings and very long and 

 fine tips. The hooks have four or five rows of small teeth above the main fang. 



