268 



Annelida Clicetopoda 



PHRONIA n. gen. 

 Head divided into palpi. Body elongate, flattened, 

 composed of numerous segments. First segment with two 

 pairs of tentacular cirri, without setae. Dorsal cirri of 

 second segment similar to the upper tentacular cirri. 

 Remaining dorsal cirri flattened, thin. Feet uniramous. 

 Setae all simple, capillary. Anal segment not seen. 



Phronia tardigrada n. sp. 



PLATE XI, FIGS. 158-163. 



Head (f. 158), width greater than length ; lateral margins 

 slightly concave ; posterior margin straight to the middle 

 third, then curving suddenly backward, encroaching on 

 the front of the buccal segment ; on the lower surface, close 

 to the inner anterior margin of the frontal lobes (palpi), 

 two minute papillae, which, pointing forward and inward, 

 project a little beyond the palpi ; in front the division be- 

 tween the palpi extends about one-third of the way back; 

 above, is continued as a shallow depression ; below, as a 

 deeply impressed line, to the posterior margin : palpi 

 broadly rounded in front. Antennae two, conical, lateral, 

 very small. 



Tentacular cirri ; superior, conical, elongate, turned for- 

 ward, reaching a little beyond the head : inferior, conical, 

 minute. Sides of the buccal segment turned forward, 

 embracing the head. The mouth has a crenulated posterior 

 margin. Dorsal cirri of the second segment similar to 

 those of the first, but a little longer and very slightly flat- 

 tened ; after the first they have a cylindrical or slightly 

 tapering basal article ; back of the second segment they 

 are suddenly shortened and flattened, becoming leaf-shaped 

 (figs. 159, 160). The substance of these cirri is crowded 

 with small glandular bodies, and those of the anterior seg- 

 ments have a series of minute cylindrical papillae along 



