206 



Annelida Chcetopoda 



Elytra, 12 pairs, completely covering the back. First 

 Dair nearly circalar, the others oval, slightly broader 

 oehind than in front (pi. I, f. 7). Posterior and outer 

 margin coarsely fringed ; an isolated patch of fringe on the 

 inner margin, not arising from the edge, but from the sur- 

 face of the elytron near the edge. Along the inner border 

 where there is no fringe, is a series of minute papillae. 

 When not macj-niiied the elvtra seem to be smooth. In 

 reality they are covered with minute, sharp, spine-like pro- 

 jections. The color of these little spines is usually reddish 

 brown, though they may be any shade of brown, or even 

 white. 



The dorsal cirri are about one-balf the length of the 

 middle antenna, and have the same form. They arise 

 from a stout basal article, much swollen along its inner 

 half: outer half cylindrical. They project by about one- 

 third of their own length beyond the setfe. The feet are 

 Jarge, in length about equal to the width of the body, 

 somewhat compressed, diameter suddenly diminishing at 

 outer third, truncated externally. Set«of dorsal ramus 

 numerous, delicate, usually covered, vdt\i a single series 

 of rather coarse denticulations (pi. 11, fig. 12). Those of 

 the lov/er ramus, stout, bidentate (pi. I, figs. 9, 10); 

 superior tooth very little curved, projecting some distance 

 beyond the inferior. Below the apex there are a few stout 

 denticles. Of the terminal teeth, the lower is fi-equently 

 worn off i pl. n, f. 13). The setae of the lower ramus are 

 somewhat variable in form, as shown in the figures. 

 Those of the first segment are not bidentate (pi. I, f. 11). 

 The ventral cirri arise at about the inner third of the feet, 

 from a small, rounded, basal article; they are minute, 

 conical (pi. I, f. 8j. There are two very long anal cirri, 

 longer than the micfdle antenna. The dorsal cirri of the 

 last segment turn directly backward, and reach about one- 



