94 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 10 



The prostomium is semicircular, anteriorly rounded, with frontal an- 

 tennae somewhat longer than usual ; they are about twice as long as wide. 

 The occipital tentacles are inserted rather far forward, leaving exposed 

 a considerable space anterior to the peristomial margin, somewhat as in 

 Onuphis parva (above). The anterior median margin of the peristomium 

 is triangular, slightly extends over the posterior margin of the pro- 

 stomium. The ceratophores are nearly smooth, the longest about twice as 

 long as wide, the shortest proportionately a little less. The inner paired 

 tentacles are the longest and thickest, extend back to the seventh or 

 eighth setiger. The median tentacle is a little shorter, extends back to 

 about the fifth setiger; the outer paired ones are the shortest. 



The peristomium (medially) is about as long as the fourth setigerous 

 ring, but is somewhat longer at the sides. Its cirri are slender, about half 

 as long as the prostomium. The first setigerous ring is prolonged, about 

 twice as long as the peristomium, and the second and third rings are 

 gradually shorter. The fourth is again about as long as the peristomium. 

 The first parapodia are the largest, directed somewhat forward, but the 

 second are only slightly smaller, with similar cirri and postsetal lobe. 

 Dorsal cirri of the first few segments are longer than those farther back, 

 and exceed in length the postsetal lobe and ventral cirrus. Ventral cirri 

 are cirriform through only 3 setigers, after that they are padlike. The 

 postsetal lobe is longest anteriorly, but continues farther back as a di- 

 minishing, triangular lobe, even into a far posterior region. 



Tridentate hooded hooks, with an articulating appendage, occur in 

 the first 3 setigers (pi. 15, fig. 315) ; setigers 4 to 11 have composite 

 spinigers (pi. 15, fig. 317) and heavy simple hooks (pi. 15, fig. 318). 

 Subacicular bidentate hooks (pi. 15, fig. 319) are present from the 

 twelfth setiger, number 2 in a parapodium, and replace the composite 

 spinigers. Pectinate setae are seemingly absent from the first 25 setigers, 

 but can be made out in all subsequent segments. A second parapodium 

 has 2 slender, bilimbate setae above and 4 tridentate, composite hooded 

 hooks. A fourth parapodium has 3 similar, simple limbate setae above, a 

 shorter, limbate seta medially, a stout, simple, hooded hook (pi. 15, fig. 

 321), 2 inferior composite spinigers, and is supported by 3 acicula that 

 are distally bulbous. An eighth parapodium has 2 bulbous acicula (pi. 

 15, fig. 322), 3 superior, limbate, simple setae, 2 similar, though shorter, 

 setae medially, and 3 composite spinigers below. A transition occurs at 

 the eleventh to twelfth setiger, after which composite spinigers are lack- 

 ing. By the fourteenth setiger there are 2 geniculate, tapering acicula 

 (pi. 15, fig. 320), 2 subacicular, bidentate, hooded hooks (pi. 15, fig. 



