406 PKOCEEDINGS OF THE ACADEMY OF [June, 



lateral tentacular ceratophores modify this form. Eyes 2 pairs; the 

 anterior large and partly on the base of the posterior lateral lobes, as 

 a consequence of which they face both forward and outward ; the pos- 

 terior are about ^ the diameter of the anterior and are situated nearly on 

 the dorsal surface close to, but slightly mesiad and caudad of, the 

 ocular lobes. 



Ceratophore of median tentacle about f as long as prostomium, 

 stout and distally swollen; style 4 times length of prostomium, slender, 

 slightly tapering, with an abrupt egg-shaped subterminal enlargement 

 having the large end distad, and followed by a terminal filament of 

 equal or shghtly greater length. Lateral tentacles similar in form to 

 the median but only about f as long, and the ceratophore only ^ as 

 long as that of the former. The colors of the tentacles are well pre- 

 served and striking in their contrast with the colorless head; the cer- 

 atophores are ringed with yellowish-brown, the basal half of the style 

 strongly tinged \\ath brown, the proximal half of the subterminal en- 

 largement deep brown, and the rest pure white. Palpi about equal- 

 ling median tentacle, rather stout, but their bases not enlarged nor 

 extending laterally beyond prostomium, gently tapering, abruptly 

 sharp pointed, but without terminal filament, densely ciliated, basal 

 half pale brown. 



Peristomial parapodium long, slender, reaching to the level of the 

 tip of the tentacular ceratophore. Tentacular cirri similar in form and 

 color to the tentacles but \vith somew^hat longer terminal filaments, 

 the dorsal equalling the median tentacle, the ventral somewhat shorter. 



There are 26 somites, of w^hich 25 bear setse and 12 elytra. The ne- 

 phridial tubercles occupy the usual position and point strongly laterad 

 and slightly ventrad and caudad ; the last pair, on XXVI, are in con- 

 tact mesially and all except the first, on VI, are prominent. 



Prominent dorsal papillae occur on all the somites from II to XX in- 

 clusive, being median on II and on X^' to XX, and in double parame- 

 dian series on III to XIV inclusive. The first one is a low, flat, nearly 

 c{uadrate nuchal tubercle which somewhat overlaps the prostomium 

 from behind ; from III to XIV each somite bears a larger anterior and 

 a smaller posterior pair; on III those of each pair are close together 

 and united by slight transverse ridges; the others are well separated, 

 the median interspace increasing in width with the segments ; somites 

 XV to XIX have each a single larger anterior and a smaller posterior 

 papilla, and XX the large one alone. 



The elytrophores are large and shaped like the body of an oyster or 

 even more like the human external ear viewed from the cephalic side. 



