1923] NATURAL SCIENCES OF PHILADELPHIA 239 



feature is variable in .V. oculatus it is probablj^ variable in this 

 species also. The bathymetrical range is noteworthy. 



Stations 4397, off Santa Catalina Islands, lat. 33° 10' 15" N., 

 long. 121° 42' 32" W., 2196-2228 fathoms, gray mud; 4454, off 

 Point Pinos Lighthouse, 65-71 fathoms, green mud and sand. 



AMMOCHARIDAE 

 Ammocharis occidentalis Johnson? 



This determination is based upon probability only, as owing to 

 the toughness of the tubes and the closeness of their contact with 

 the worms, the latter are in a poor state of preservation and cannot 

 be extracted. The uncini are bifid as in Johnson's species but are 

 colorless. Capillary setae are fringed at the tips only. 



A tube is 90 mm. long and 2.5 mm. in diameter and covered 

 with small fragments of shells arranged in the usual imbricated 

 manner. 



Station 4496, off Santa Cruz Lighthouse, 10 fathoms, fine gray 

 sand and rocks. 



SABELLIDAE 

 Branchiomma circumspectum sp. nov. Plate XVIII. figs. 41, 42 



Known and described from the type only, — a well-preserved 

 specimen 31 mm. long, of which the gills are 6 mm. and the thorax 

 5.5 mm., the maximum width of the thorax being 1.8 mm. Seg- 

 ments, thoracic 9 (8 setigerous), abdominal 59. 



Branchial bases simple, low, of even height, slight I3' prolonged 

 ventrally but not coiled, well separated dorsally. Radioles fourteen 

 pairs, the ventral pair rudimentary, cleft and separated nearly 

 to the base, no interbranchial membrane, rounded on external 

 face and totally destitute of marginal expansions, rather thick and 

 gently tapered, the dorsal pair being somewhat thicker and of 

 almost uniform diameter. Barbs also rather short, thick and stitf, 

 the longest about one-third width of thorax, a short distal portion 

 of the radioles free from them. At this point where the barbs 

 cease are situated the compound eyes, a single one on each radiole 

 facing toward the center of the circle formed by the gills. Eyes 

 subsphcrical, enclosing the radiole internally, laterally and except 

 for a narrow cleft, externallj^ swelling prominently internally. 

 They are deep brown and very conspicuous but vary in size. 

 Generally they are about etjual to th(^ greatest diameter of the 

 radiole bearing them and about twice tiie diameter of the end of 

 the filament liut they decrease in size ventrally, the ventralmost 

 on the immature radioles l^eing scarcely visible. The dorsalmost 



