202 PROCEEDINGS OF THE ACADEMY OF [Vol. LXXV 



by a narrow ridge with the setigerous tubercle of VI. One speci- 

 men (the type) has three gills in place, each having a length of 

 three times the width of the thorax and in form inflected, rather 

 thick and tapering to acute tips. 



Thorax of twenty segments, of which III bears paleoli and the 

 following seventeen true setae fascicles. Up to X, the segments are 

 short and crowded and bear distinct gland plates. Behind X, 

 they become elongated and the gland plates undergo reduction in 

 size and become scarcely discernible. 



Abdominal segments ten, tapering, the dorsal cirri nearly 

 obsolete. Pygidium slightly quadrilobate, the ventral pair of lobes 

 bearing short stiff cirri at their dorsal margins. 



The paleoli on III form an inconspicuous tuft of nine or ten very 

 small flattened spines no larger than the true setae on IV. They 

 project forward and are very acute, alimbate, and longitudinally 

 striated. True setae tufts, except the first three, are rather promi- 

 nent, the tubercles borne on a pronounced lateral longitudinal 

 ridge. Each tuft consists of ten or twelve pairs of larger and smaller 

 tapering narrowly limbate setae. Counting 3 prebranchial segments, 

 the tori begin on VII, the anterior being largest, but all remarkably 

 small, as in Sanii/tha, their width not exceeding | or even yV of 

 the segment. X bears about 60 to 70 small uncini (Plate XVII, 

 figs. 11, 12) having one large hooked tooth below and three or four 

 irregular rows of three to five smaller teeth above, with a marginal 

 arch of still smaller teeth. In fig. 11, the lowermost tooth is worn 

 down. Abdominal tori also small narrow lappets rounded at the 

 border and with a simple slightly developed dorsal cirrus separated 

 from the torus by the width of the lateral ridge only. Abdominal 

 uncini (fig. 13) similar to thoracic but smaller, with the crest teeth 

 in a crowded tuft of three rows of three or four each. 



All three specimens are too soft to permit of a complete des- 

 cription. The only complete one is 27 mm. long, about 2 mm. in 

 maximum diameter, elongated fusiform and consists of thirtj^ 

 segments. All three contain eggs. 



Stations 4387, lat. 32° 32' 40" N., long 118° 04' 20" W., 1059 

 fathoms, green mud; 4431, off Santa Rosa Island, 38-45 fathoms, 

 green and yellow mud, etc. (type) ; 4436, off San Miguel Island, 

 264-271 fathoms, green mud. If these soundings are correctly 

 recorded this species has the rather remarkable bathymetric range 

 of more than 1000 fathoms. 



Amphicteis scaphobranchiata Moore. 



Several well-preserved specimens agree fully with the types of 

 this very distinct species. Full grown and mature individuals, 

 some of which contain eggs or sperm, measure 33-54 mm. and have 



