196 THE ANNELIDA POLYCHAETA. 



Hedyle Malmgren was also based upon an epitokous form of a species of 

 Perinereis. Included under Perinereis are also Malmgren's genera Lipephile 

 and Stratonice. Nereilepas and Hediste have by some authors been so con- 

 ceived as in part to cover this genus; but their types carry them to Nereis. 

 Arete Kinberg is kept apart here tentatively but is quite likely also to have to 

 be included ; and Perinereis may in turn possibly have to be united with Pseudo- 

 nereis. 



Leontis Malmgren and Iphinereis Malmgren (based on the epitokous stage) 

 are the same as Platynereis Kinberg. 



Nicon Kinberg and Nicomedes Kinberg are synonymous with Leptonereis, 

 the former also being preoccupied (Gray, Mammals, 1847). Alitta Kinberg is 

 regarded as not differing generically from Neanthes Kinberg. 



Lycastis Savigny (Descript. Egypte. Hist, nat., 1809 [= 1822], 1, pt. 3, 

 p. 45) was proposed for Nereis armillaris O. F. Miiller; but as this species 

 proves to belong under Syllis in the Syllidae, the nereid generic group to which 

 Lycastis has long been applied remains without a name. To supply the lack 

 Namanereis is proposed with N. quadraticeps Gay as the type. 



Kainonereis, gen. nov.^ 



Prostomium short and narrow, narrowed cephaloventrad. Tentacle long, 

 single, bifid at tip, varicose or annulated (male). Palpi reduced; biarticulate; 

 with proximal article stout, the distal more slender and soft. 



Four eyes, large, the two of each side close together, the anterior more lateral 

 in position, the posterior more dorsal and on caudal region of prostomium. 



Nuchal organs simple, ciliated pits. 



Peristomium with four pairs of tentacular cirri which are varicose or annu- 

 lated (male). 



All parapodia biramous, each branch supported by a single, stout aciculum. 

 Dorsal branch with two ligulae, the ventral with one. Setae all compound. 

 Shafts strongly cross-striate. Neuropodial setae of anterior, or nereis region, 

 falcate and setose. The notopodials in the anterior part of this region coarser 

 and darker, with the distal piece short and distally blunt. Both dorsal and 

 ventral cirri present. The notocirrus in anterior region expanded proximally 

 and on some with the expanded region very large (fifth, sixth, and seventh pairs 

 in type), forming elytra-like organs. Both notocirri and neurocirri in the 



' Kat.v6s, unusual, and Nereis. 



