230 BUSH 



Setae of the collar fascicle of two forms, long slender limbate and 

 others with broad spinous basal fin (p1. xl, fig 22). Other fascicles 

 with shorter and broader limbate setae. No capillary ones, as in 

 Spirorbis. 



Uncini with numerous teeth, the lowest one larger than the others. 



Abdominal setae small, trumpet-shaped, with a long tapered end. 



Total length of largest specimens between 15 and 20 mm. ; breadth 

 about .5 mm. Smallest specimen about 5 mm. 



Virgin Bay, Prince William Sound, June 27, eight specimens. 



SERPULA SPLENDENS sp. nov. 



p1. XXVI, fig. 3 ; pi. XXIX, fig, 2 ; pi. XXX, figs. 2, 3 ; pi. xxxiii, fig. 31 ; 

 pi. XXXV, fig. 18; p1. xxxvii, fig. 31 ; p1. xxxix, fig. 33. 



Type locality. — Prince William Sound, at Orca and Virgin Bay. 



Color in formalin yellowish, with the branchiae and operculum vari- 

 ously banded and mottled with deep crimson, which in life is a ' bril- 

 liant red.' 



Thoracic membrane with a very wide margin overlapping on the 

 back and forming a very deep rolling collar with a median ventral and 

 two lateral incisions. 



Branchial lobes with comparatively small basal attachment, arch- 

 ing obliquely forward, curving inward ventrally, thickest below and 

 strengthened by a conspicuous tapered median rib, and in front, at the 

 end, by a large rib reaching backward inside the collar. Between 

 these end ribs and attached to them is a broad, gradually widening, 

 muscular band curving inward between the bases of the lobes, forming 

 a trumpet-shaped process over the mouth ; above this is a thin, some- 

 what ruffled membrane, which extends out on each side around and 

 inside the lobes, attached to their bases ; extending forward and inward 

 from the dorsal furrow is a tongue-shaped process, free at the end, hav- 

 ing a granular surface, which completely covers the end of the trumpet. 



Branchiae short, between 45 and 50 pairs, their tapered rachises 

 rounded outwardly, with short filamentose tips, the two inner edges 

 bearing long well-separated pinnae ; a few of the extreme ventral 

 branchiae extend around the end of the lobe and backward or inward 

 along its edge. 



Opercula two ; the primary one thin, large, deep funnel-shaped, 

 with numerous delicate branching radii, forming a finely serrate (be- 

 tween 137 and 150 serrations) margin, the inner surface often with 

 minute scattered tubercles ; base globular, without processes, attached 



