134 DISCOVERY REPORTS 



cirrus. The normal dorsal cirri are about half as long as the body is broad. All the 

 modified segments carry swimming bristles (Fig. 23). There is a large rounded supra- 

 chaetal lobe. 



Otherwise there is nothing remarkable about the normal feet and bristles. The bristles 

 are of the usual type, with the heads of the shafts denticulated and with the end-pieces 

 very short and clearly bidentate. 



Remarks. I suspect this specimen of being the Polybostrichus of Aiitolytus gibber, 

 Ehlers. It is clearly different from the Polybostrichus oi A. simplex which is represented 

 in the present collection. Nuchal epaulettes are present in the Polybostrichus of 

 A. charcoti, and according to Ehlers (191 3, p. 490) the Polybostrichus of A. maclearomis 

 has a very differently shaped head with the median tentacle set in front of the dorsal 

 eyes. The Polybostrichus oi A. longstaffi, Ehlers, of which the atocous form is not known, 

 has a head rather like that of the present specimen, but in the anterior region only the 

 first six instead of the first 14 chaetigers remain unmodified. Autolytiis gibber, Ehlers, 

 is the only other Aiitolytus described from these waters, and it seems a probable assump- 

 tion that the present specimen belongs to that species. 



Family NEREIDAE 



1. Without paragnaths Leptonereis 



With paragnaths ... ... ... ... ... ... ... ... • • • • • • • • • 2 



2. Horny paragnaths arranged in pectinate rows Platynereis 



Homy paragnaths conical and separated ... ... ... ... ... ... Nereis 



Genus Nereis, Cuvier 



Body elongate and vermiform. Two ovoid palps, two tentacles and four pairs of 

 tentacular cirri. Proboscis with separate, conical, horny paragnaths usually arranged 

 in distinct groups. The feet are biramous. The bristles are compound and the end-pieces 

 are either long, sharply pointed processes (spinigers) or relatively short, more or less 

 curved blades (falcigers). 



1. Without paragnaths on the maxillary ring ... (Subgenus Eunereis) N. (Eunereis) hardyi 

 With paragnaths on the maxillary ring... ... ... ... ... ... .•• •■• 2 



2. With homogomph falcigers in the notopods of the hinder region ... ... ... ... 3 



Without homogomph falcigers in the notopods of the hinder region ... ... ... 4 



3. Hinder notopodial falcigers bidentate or tridentate ... ... ... ... N.jacksoni 



Hinder notopodial falcigers with simple, blunt tips ... ... ... ... N.eugeniae 



4. Paragnaths of oral ring in a single row. . . A'^. kerguelensts 



Paragnaths of oral ring in several rows... ... ... ... ... ... ... ... 5 



5. Paragnaths of oral ring a continuous band ; three notopodiallanguets ... N . cricognatha 

 Paragnaths of oral ring discontinuous ; two notopodial languets ... ... A^. callaoana 



Nereis (Eunereis) hardyi, Monro. 

 Monro, 1930, p. 109, fig. 39 a-d. 



■ Occurrence. St. WS 755 (2); WS 756 (i); WS 797 (10); WS811 (2); WS 834 (numerous); 

 WS 841 (i); WS 847 (3); WS 848 (10). 



