256 bulletin: museum of comparative zoology. 



12. Nereis brandti Malmgren. 



Ofvers. K. vet. akad. Forh., 1865, p. 183. 



Sacramento Bay (Capt. H. Davis, April, 1859), San Mateo, Calif., 

 and Gulf of Georgia, Wash. (A. Agassiz). 



13. Nereis vexillosa Grube. 



Middendorf's Reise nord. u. ost. Siber. Zool., 1851, 2, th. 1, p. 4, pi. 2, fig. 4, 

 5,6. 



Mendocino, Crescent City, and San Mateo, Calif., and at the 

 Gulf of Georgia, Wash. (A. Agassiz). 



14. Nereis mendocinana, sp. nov. 

 Plate 1, fig. 5. 



'b* 



In this species the notopodia are simple, none at all enlarged into a large 

 lamellar form bearing the cirrus such as occurs in brandti and vexillosa. The 

 two lobes of the notopodia are equal throughout. In a considerable number 

 of the anterior notopodia the lobes are thick and conical; but caudad they 

 become more slender and thin in the anterocaudal direction, in the posterior 

 region appearing as simple, short triangular processes. Notocirrus attached 

 at base of dorsal lobe, long and slender or filiform. No postsetal lobe in the 

 anterior parapodia but caudad one becomes evident as a low, but broad, dis- 

 tally straight or slightly convex tip. Lower neuropodial lobe conical, nearly 

 the same size as the notopodial lobes, becoming smaller and more slender 

 caudad. Neurocirri arising from swelling at base of neuropodia, slender, sur- 

 passing neuropodial lobe. Anterior region of prostomium triangular with 

 anterior end narrowly truncate and bearing the tentacles which are contiguous, 

 subulate, and shorter than the distance between eyes. Eyes large, the poste- 

 rior eye on each side in line with the anterior or nearly so, smaller. Styles 

 of cirri short, articulated. In the proboscis I is unarmed. Each II bears nine 

 or ten teeth in a double oblique line. V is unarmed. Each VI bears a few 

 denticles in a central area. On each IV there are ten teeth, of which eight 

 or nine form a curved line while one or two lie on the concave side of this. 

 On the ventral side across VII and VIII run several series of denticles of which 

 those of the most anterior series are fewer, more widely separated and much 



