1903.] NATURAL SCIENCES OF PHILADELPHIA. 403 



The parapodia are long and slender and especially so toward the 

 caudal extremity. Neuropodiiim conical, divided terminally into pre- 

 and post-setal lobes, both prolonged dorsally, and the former the larger; 

 ventral surface studded with large spherical papillae on short stalks. 

 Notopodium a small, slender, freely projecting process supported by 

 a distinct aciculum. Dorsal cirri with small ceratophores, and long, 

 slender, regularly tapered styles which reach considerably beyond 

 the setse tips anteriorly, but posteriorly, owing to shortening of the 

 cirri and lengthening of the feet, fall short of the setse tips. Ventral 

 cirri short, less than ^ dorsal, thick basalty and slender terminally; pos- 

 teriorly they undergo the same relative change of position as the dorsal, 

 and for the same reason. 



Only about i of the total number of elytra are in situ and are very 

 easily detached, but the elytrophores indicate 25 pairs placed on the 

 following somites: II. IV. V, then on alternate somites to XXIII, then 

 on XXVI, XXIX, XXXII and XXXIV, and after that on every third 

 somite to LXI. They are small, leaving a large portion of the back 

 exposed, delicate and usually much distorted, nearly circular, with 

 central attachment ' and quite without papillse or hairs of any kind; 

 the medial half is reddish-brown, the lateral unpigmented. 



Notopodial setse are totally wanting, but there is a relatively stout 

 tapering aciculum. The neuropodial setse are disposed in about 9 

 close rows; all are nearly colorless and rather slender. Those of the 

 dorsalmost row or two form a distinct group which project beyond the 

 others, and probably serve somewhat the purpose of the notopodial 

 setse of other species ; their shafts are scarcely more than h the diameter 

 of the other neuropodials and the ends are much prolonged and pro- 

 vided with close transverse rows of fine hairs quite to the simple tips. 

 The others have the usual form, the more dorsal ones with simple tips 

 and as many as 14 transverse combs, the middle and ventral ones with 

 a more or less prominent accessory tooth at the tip and shorter 

 enlarged ends with as few as 8 combs on the most ventral setae. 



Sagami Bay, 3.698, 153 fms. 

 Scalesetosus formosus sp. nov. (PL XXIII, figs. 4, 5. 6.) 



This s})ecies is referred to Mcintosh's genus on account of the form 

 of the head and neuropodial setse, the latter being very characteristic ; 

 in many other respects it departs widely from the generic type. The 

 single example on which the description is based is complete, but 

 broken into three pieces, and with the scales detached. At the poste- 

 rior end is a small regenerating piece, but the form of that region, and 

 especially the structure of the parapodia, indicates that it is of prac- 



