216 THE ANNELIDA POLYCHAETA. 



Proboscis armed with numerous corneous paragnatha arranged in close 

 series (pectinate) as in Platynereis. 



Genotype. — U. suhita, sp. nov. 



In addition to the type-species, Nereis agassizi Ehlers, and apparently also 

 A"", notomacula Treadwell and N. kobiensis Mcintosh fall into this genus, of 

 which the most salient distinctive character is the presence of the hooked setae 

 or crochets in the notopodial fascicles. These are much hke those present 

 in lumbrinereids, but are not known to me to occur in other species of Nereis, 

 Platynereis, or related genera. The species of Uncinereis agree closely also 

 in various other characters. All at present known are from the Pacific. 



Uncinereis subita, sp. nov.^ 

 Plate 30, fig. 1-4. 



The general color of the preserved specimens is a dense brown. The ten- 

 tacles and cirri are much fighter, yellowish. 



The type is incomplete caudally. It consists at present of sixty somites 

 and has a length of 22 mm., with a maximum width, exclusive of the parapodia, 

 of 1.8 mm. The body is widest and highest in the r^^gion of the fifth somite, 

 from where it narrows and lowers cephalad and, more gradually, caudad in the 

 usual way. 



The prostomium is nearly equal in length and breadth. It is widest near 

 the middle at the level of the anterior eyes from where it narrows a little caudad 

 and more strongly cephalad, with the anterior end widely subtruncate, being a 

 little more extended forward at middle than at end, and in outline appearing 

 much like that of U. kobiensis (Mcintosh). The preocular region is flattened 

 above and depressed below the level of the broader posterior region. The eyes 

 are nearly equal in size. The posterior ones are only slightly nearer together 

 than the anterior and have their axes directed more dorsad. The posterior 

 and anterior eyes on each side are nearly contiguous. The tentacles are not 

 contiguous proximally. They are moderately long, a fittle exceeding the length 

 of the prostomium, and are slender and gradually acuminate distad as usual. 

 The palpi are nearly as long as the tentacles. The proximal article is about 

 as thick as the width of the prostomium across its anterior end. The distal 



' subire, to go under, descend. 



