1909] Torrey-Kleeberger: Three Species of Cerianthus. 125 



The mesenterial filaments are tightly coiled on the shorter 

 mesenteries — of the third and fourth orders. The gonads, her- 

 maphroditic, as in C. In mih ni, arc borne on mesenteries of the 

 first, second, and frequently third, orders. 



The acontia-like processes of the mesenterial filaments are 

 similar in structure to those of C. benedeni, with the one excep- 

 tion that they lack the cnidorages characteristic of that species. 

 They are bunched at the oral ends of the mesenterial filaments 

 on tin- shorter mesenteries, and they are separated along the 

 edges of the mesenteries of the first and second orders, being 

 concentrated somewhat just below the lower limit of the mesen- 

 terial filaments of the second order of mesenteries. 



The species most closely allied to the San Pedro form is the 

 European C. membranaceus. The two agree in all characters 

 except, possibly, the length of the directives, the arrangement of 

 the other mesenteries associated with the siphonoglyph. and the 

 coloration. On this basis, they are provisionally distinguished. 

 From the Atlantic American C. borealis and ('. americanus, 

 ('. johnsoni is distinguished at once by the fact that hut a single 

 pair of mesenteries approximates the terminal pore. 



Zoological Laboratory, 

 University of California. 

 Mini 18, 1909. 



