246 PROCEEDINGS OF THE ACADEMY OF [April. 



Pygidium minute, top-shaped, bearing a pair of rudimentary para- 

 podia, two pairs of short ventral subanal cirri and a whorl of slender 

 papillae. 



Parapodia of anterior region similar in general characters and setae 

 to atokous type of corresponding segments. Notopodia of first seven 

 with basal half much enlarged, the distal portion remaining filiform, 

 but not strongly bent. Neurocirri of first five setigerous segments 

 also thickened at the base. All remaining parapodia are modified to 

 the natatorial type, there being no caudal region, but the serrated 

 notocirri continue to about XLV only, behind which they are smooth. 

 The form of the complex lamellae and lingulae is best understood by 

 reference to figure 18 (PI. XV). All setae are of the usual natatorial 

 type and none of the peculiar setae so characteristic of the middle 

 notopodia of atokous individuals are present. 



One specimen has the proboscis protruded and exhibits the para- 

 gnaths and jaws in characteristic arrangement. 



Stations 4,355, San Diego Harbor, surface; 4,405, off San Clemente 

 Island, 654-704 fathoms, green mud; 4,415, off Santa Barbara Island, 

 302-638 fathoms, green mud; 4,417, off Santa Barbara Island, 29 

 fathoms, fine yellow sand and rock; 4,420, off San Nicolas Island, 

 32-33 fathoms, fine gray sand; 4,421, same locality, 229-298 fathoms, 

 gray mud and rock; 4,425, same locality, 1,100-1,084 fathoms, green 

 mud, fine sand and Globigerina; 4,427, off Santa Cruz Island, 447-510 

 fathoms, black mud and rock; 4,431, off Santa Rosa Island, 38-41 

 fathoms, varied bottom; 4,496, off Santa Cruz Lighthouse, Monterey 

 Bay, 10 fathoms, fine gray sand and rock; 4,531, off Point Pinos 

 Lighthouse, 26-28 fathoms, fine gray sand, rock. 



Nereis pauoidentata Moore. 



Nereis paucidentata Moore. Proc. Acad. Nat. Sci. Phila., 1903, pp. 430, 431, 

 PI. XXIV, figs. 28-30. 



A single small imperfect specimen fromstation4,397,Lat.33°10'15"N. 

 Long. 121° 42' 15" W., 2,196 fathoms, gray mud. This is the first 

 record of this species south of the Gulf of Georgia and the bathymetrical 

 range is even more extended from 270 fathoms. The species is not 

 uncommon in Alaskan waters. 



Nereis cyolurus Harrington. 



Nereis cyclurus Harrington, Trans. N. Y. Acad. Sci., XVI, 1S97, p. 214. 



Two fine specimens showing faintly the annular bands of color. 

 "Commensal in Natica shell with hermit crab." 



Station 4,560, off Santa Cruz Lighthouse, Monterey Bay, 10-12 

 fathoms, fine gray sand and rock. 



