266 PROCEEDINGS OF THE ACADEMY OF [April, 



portions are composed mainly of fine silt, but sometimes with a few 

 sand grains or minute pebbles. 



This appears to be an abundant species, and were it not for its small 

 size would doubtless have been collected at many more stations. It 

 was especially abundant at stations 4,467 and 4,468, where several 

 hundred tubes were taken, and at 4,475, where about fifty were 

 obtained. 



Stations 4,445, off Point Pinos Lighthouse, Monterey Bay, 60-66 

 fathoms, green mud ; 4,446, same locality, 52-59 fathoms, green mud 

 (type) ; 4,452, 4,453, 4,454, same locality, 49-71 fathoms, green mud 

 and sand; 4,457, same locality, 40-46 fathoms, dark green mud; 

 4,464, same locality, 36-51 fathoms, soft dark gray mud; 4,467, off 

 Santa Cruz Lighthouse, Monterey Bay, 51-54 fathoms, soft dark 

 green mud; 4,468, same locality, fine sand; 4,475, off Point Pinos 

 Lighthouse, 58-142 fathoms, soft green mud; 4,480, off Santa Cruz 

 Lighthouse, 53-76 fathoms, dark green mud and sand; 4,485, same 

 locality, 89-108 fathoms, soft green mud and sand; 4,510, off Point 

 Pinos Lighthouse, 91-184 fathoms, gray mud; 4,522, same locality, 

 130-149 fathoms, gray sand and shells; 4,523, same locality, 75-108 

 fathoms, soft dark mud. 



Onuphis vexillaria sp. nov. PI. XVII, figs. 69-76. 



A slender, elongated and very distinct species described from a 

 single anterior end and four other pieces which are believed to form a 

 single specimen, complete except for the caudal end. The aggregate 

 length is 159 mm., the width without parapodia 3 mm. and including 

 them 4.2 mm. in the middle region ; and the total number of segments 

 242. 



Prostomium small, nearly circular, with a slight posterior emargina- 

 tion, convex, its surface largely occupied by the bases of the tentacles, 

 which are arranged in the form of an ellipse. Frontal tentacles short, 

 thick and ovate, about one-half length of prostomium, short peduncu- 

 late, divergent and separated by a space exceeding their diameter. 

 A pah" of minute eye-spots at the medial side of their bases. Dorsal 

 tentacles all with annulated ceratophores and slender smooth styles. 

 Anterior pah* reach to middle of III, the style three times the length 

 of the ceratophore which has seven articulations. Posterior pair 

 reaching X, the ceratophore as long as the anterior but with a smooth 

 distal part in addition to seven articulations. Median reaching VIII 

 with much shorter ceratophore of six annuli. Palps immediately 

 anterior to mouth, strongly divergent, stouter and somewhat longer 

 than frontal tentacles and divided by a shallow cross-furrow. 



