191'''] Esscnherg : New Species of Folynoidae 47 



from a holothnrian, Stichopus calif ornicus, were brown in color, while 

 the specimens found on the key-hole limpet Lucapina crenulaia were 

 dark, with conspicuous black rings on the elytra. At certain times 

 the body of the worm may be filled with ova and greatly expanded, 

 giving the worm a different appearance. The elytra do not extend far 

 enough in that case to cover the entire dorsum. 



However, some characteristics are constant, furnishing a reliable 

 basis for classification. Among these are the shape and the relative 

 size of the prostomium, the size and location of the eyes, the relative 

 length and structure of the cirri and of the palpi, the structure of the 

 setae, the shape and relative size of the corresponding parapodia, and 

 to some extent the number and structure of the elytra. The last 

 characteristic may not be true of long worms, such as Lepidosthenia 

 gigas. The number of elytra may vary in this ease in different 

 individuals. 



The Polynoidae are voracious feeders, attacking one another when 

 in captivity. The writer had a number of specimens of Polynoe cali- 

 fornica in an aquarium, where the food supply was scarce. The worms 

 attacked one another with their strongly developed jaws, displacing 

 the elytra or removing entire posterior segments of their companions. 



The material used in this work was from the annelid collection of 

 the Zoological Museum of the University of California at Berkeley. 

 In the material of that collection some species were found that had 

 not been mentioned previously in Treadwell's (1914) summary of the 

 polychaetous annelids of the Pacific Coast. These were: Polynoe com 

 planata Johnson, which I found labelled Harmothoe imhricata, and 

 a number of specimens of Halosydna lagunae Hamilton, which 

 were labelled as Lepidonotus caelorus. Halosydna carinata Moore, 

 reported by A. Treadwell (1914) as being in the collection, was not 

 there ; some specimens labelled Harmothoe carinata did not agree 

 with the characteristics of Harmothoe carinata. The writer had the 

 opportunity of comparing a specimen of Harmothoe carinata, which 

 Dr. J. P. Moore had the kindness to send to us, with the specimens 

 labelled Harmothoe carinata Moore, in the Zoological Museum at 

 Berkeley. Some Eunoe harhata were found labelled as Harmothoe 

 crassicirrata. 



