"290 ANNELIDA POLYCHiETA ANDREWS. 



The immense jelly masses, in which the somewhat salmon-colored 

 eggs are laid, protrude from the burrows of the Annelids, and subse- 

 quently are washed about from place to place as the larvae develops. 



The number of eggs thus laid by one individual was estimated as 

 three hundred thousand. 



Their development has been noted by Professor Wilson in the paper 

 previously referred to. 



The colors when alive vary, but in general the body is greenish yel- 

 low ; thebranchiiT dark red; the seta? yellow, though sometimes nearly 

 black anteriorly. 



When expanded the animal measures at least 12 inches, with a diame- 

 ter of above one half an inch. 



The head is very small, dark flesh color, and may be entirely re- 

 tracted and concealed. 



Family CH^TOPTEEIDiE. 



CHiETOPTERUS Cuvier. 



Chaetoptei'us pergamentaceua Cuvier. 



AuDOUiN AND Milne Edwards. Classification des Ann^lides. >Ann. Dea. Sci. Nat., 

 ser. 1, vol. 30, p. 417. PI. xxii, Figs. 1-4. 



This remarkable Annelid is known to occur upon the New England 

 coast also, being in part figured, with the larvte also, by Professor Ver- 

 rill in the Trans. Conn. Acad., vol. 4, PI. xvii, and elsewhere described 

 as occurring near Woods HoU, Mass. The development has been 

 studied at Beaufort by Professor Wilson. Artificial fertilization is 

 easily eflected, and the habits of the adult well studied when kept in 

 aquaria, each inside a glass tube of proper diameter. They then build 

 out the ends by funnels of secreted parchment-like material. Left out 

 of tubes the animal soon dies, becoming emaciated, with great loss of 

 mucus. 



The body is brilliantly phosphorescent, and this is easily seen to be 

 due, as has been observed in Europe, to the presence of phosphorescent 

 granules or minute bodies in the mueus secreted by the epidermis; 

 this material shining brightly some time after its removal from the 

 body, and hence not directly dependent upon nervous action. 



The individuals I have since observed at Woods HoU, Massachu- 

 setts, however, do not exhibit any phosphorescence at all. 



The peculiar chimney-like, upright ends of the U-shaped tube of this 

 Annelid are rather easily found by looking over the flats, from a hori- 

 zontal position, by proper illumination ; but are found only in certain 

 restricted areas, where the sand is mingled with mud and somewhat 

 overgrown with eel-grass. In such areas on Bird Shoal and Shark 

 Shoal, at extreme low-water mark, colonies of numerous individuals 

 are found. 



In these tubes occur the commensal crabs, Porcellana and Pinnixa, in 



