so THE ANNELIDA POLYCHAETA. 



Apheodita defendens, sp. nov.^ 



The prostomium is a little longer than wide, shortly inversely subpyriform, 

 being widest in front. Convex above and in front. On dorsal surface toward 

 anterior end are two slight rounded tubercles, but no eyes could be definitely 

 discovered in the types; if present, they are colorless and obsolete. The median 

 tentacle in the type is very short and clavate, apparently representing only the 

 ceratophore; but in the paratype the style is present as a long slender filament 

 nearly equalling the prostomium in length. The short basal segment of palpi 

 narrow, less than half the width of prostomium; the main part widening from 

 base to or beyond anterior edge of facial tubercle and then regularly tapering 

 and distally becoming slender, seven times or more the length of the prostomium, 

 bearing numerous distinct sensory papillae. The facial caruncle prominent, 

 compressed laterally and running to an acute edge cephalad, the dorsal surface 

 strongly roughened, somewhat tubercular. 



Peristomial parapodia laterally compressed, lying close against parapodium 

 and proximal part of palps ; the parapodia proper surpassing the prostomium by 

 less than one and a half the length of the latter. Tentacular cirri arising near 

 distal end on ectal side, the dorsal stouter than the ventral. Setae of peristomial 

 parapodia all capillary, in flat tufts. Lower lip an elongate lobe as usual, 

 occupying middle region of II and III and pressing against IV; its sides incurved. 



Metastomial somites beneath a little convex laterally with greater part 

 between nearly flat. Very clearly separated from each other by transverse 

 folds and from the parapodia by the usual deep furrow. Surface densely crowded 

 with papillae which are commonly even more dense and conspicuous on the 

 parapodia. 



The elytra are large, widely overlapping and wholly covering the dorsal 

 region of body and head. They are smooth, and rather thin but tough. The 

 fimbriate organs rather small, widest at base, convexly narrowing distad, the 

 edge with few, well-separated but blunt processes. 



Neuropodia of middle region about one third, or a Uttle less, the width of 

 the somites. Neurocirrus of typical parapodium arising in usual position from a 

 low elevation or transverse ridge; short, slenderly subulate, just attaining bases 

 of ventral series of setae, no sub terminal knot. The notocirri long and slender 

 filaments ordinarily passing through and lying upon the felt. They lack terminal 

 and sub terminal enlargements. 



' defendere, to ward off or defend. 



