1 30 HABITUDES AND ATTITUDES 



on the part of another species, Eunice fucata, 

 was described by A. G. Mayer (1900); and 

 later still a Japanese palolo, belonging to a 

 different family (Nereidae), was described under 

 the name Ceratocephale osawai by Izuka. The 

 last-named author 1 says that the swarming of 

 the Japanese worm takes place in October and 

 November during the nights closely following 

 the new and the full moon, and it resembles 

 that of the Atlantic and Pacific species in its 

 general course, but differs in the circumstance 

 that whereas in the species of Eunice the sexual 

 segments occupy the posterior portion of the 

 body which becomes detached from the head- 

 end at the time of swarming, in the Japanese 

 worm the sexual segments are confined to the 

 anterior portion which, at the swarming season, 

 sheds the posterior, shrunken, asexual segments. 



Amongst the numerous methods of brood- 

 nursing or care of eggs and young, we meet 

 with some extraordinary cases of convergence 

 of varying degree. Frequently they are obvious 

 enough, but that very fact only serves to 

 strengthen the argument which I am endeavour- 

 ing to develop, that convergence is not a sub- 

 ordinate but a dominant factor in morphology. 

 Firstly, let us take the phenomenon of buccal 



1 Akira Izuka, " Observations on the Japanese Palolo," Journ. 

 Coll. Sci. Imp. Univ,, Tokyo, 1903, vol. xvii., article n, pp. i-37> 2 

 plates. 



