1906.] NATURAL SCIENCES OF PHILADELPHIA. 219 



In the middle region they exceed one-fourth of the entire width. They 

 consist of a broad base, a somewhat flattened, tongue-shaped neuro- 

 podium, slightly cleft at the tip and bearing a rounded and swollen 

 prominence on the ventral side of its base, and a minute papilliform 

 notopodium, which diverges dorsally from the neuropodium. Each 

 division is supported by a single aciculus, the notopodial being very 

 slender and curved, the neuropodial stouter and straight. 



Along the posterior face of the base of the neuropodium above the 

 papilla mentioned arises a flange-like ceratophore bearing a large, 

 foliaceous palette-shaped ventral cirrus which curves upward behind 

 the neuropodium and completely conceals both it and its setae from 

 behind. The notopodial ceratophore is very large, causing the 

 notopodium itself to appear as a mere appendage. At its dorsal side 

 the free distal border is prominently produced, thus prolonging the 

 surface of attachment of the notopodial cirrus. The cirrus itself is 

 very prominent, of a somew^hat irregular reniform outline and attached 

 by the marginal sinus. All of the notopodial cirri are turned nearly 

 horizontally and overlap on the back in an imbricate fashion, closely 

 similar to the elytra of the Polynoidoe. Anteriorly the dorsal cirri 

 diminish in size so that they fail to cover the back completely and 

 their ceratophores become more slender and elevated. The ventral 

 cirri also become smaller, but remain prominent as far forward as III 

 without essential change of form or position. A minute neuropodial 

 tubercle exists on II, but it is uncertain if setae are present thereon. 



The eyes are purplish brown and the general color of the body a 

 distinct dull greenish olive. Little pigment remains in any part of the 

 body, but the notopodial cirri are more or less marked wdth dusky 

 streaks and spots. A few small ova float free in the body cavity. 



The notopodium usually bears but a single slender, curved and 

 simple seta, and even this appears to be absent from several of the 

 anterior parapodia. Neuropodial setae are numerous, upwards of 20 

 to 30 occurring in the subacicular and 12 to 18 in the supraacicular 

 groups. They are colorless and transparent, compound, with the 

 stem gently curved and slightly enlarged at the end, where each side 

 of the socket is provided with 6 to 8 very long, slender teeth and several 

 shorter ones. The blade is slightly curved and tapers to an acute tip, 

 and is striated and provided with minute marginal denticulations 

 (fig. 3). 



The only specimens are the two from Station 4,269, Afoqnak Bay, 

 14 to 19 fathoms, hard gray sand and rocks. 



