42 THE ANNELIDA POLYCHAETA. 



diameter. The ceratophore of the median tentacle is longer and much thicker 

 than those of the laterals and narrows moderately distad; the style is long and 

 slenderly uniformly tapered, reaching to the sixth somite. The ceratophore of 

 each lateral tentacle is contiguous proximally with that of the median, narrows 

 distad so as to have the form of the frustum of a cone, and projects cephalo- 

 ectad; the style is clearly less than half as long as the median and reaches 

 only to the second somite. The palpi are long and cyUndrical, narrowing gradu- 

 ally toward the end and then more abruptly into a much more slender tip. 

 They greatly exceed the lateral tentacles in length. (Plate 7, fig. 3) . 



The tentacular cirri, that is, the cirri of the peristomial parapodia, are 

 attached at a level a little caudad of the middle of the prostomium. The dorsals 

 and ventrals are equal in length, which much exceeds that of the median ten- 

 tacle, reaching to the eighth or ninth somite. 



The metastomial somites are strongly convex above, more flattened ven- 

 trally. The first above is produced forward at the middle into a triangular 

 tongue extending over the caudal border of the prostomium and fitting in the 

 iniddorsal furrow of the latter. These somites increase in length to the fifth 

 or sixth in which the length is equal to that of the prostomium and the width 

 about two and a third times the length. In the seventh or eighth somite from 

 the caudal end the width is scarcely or not at all more than one and a half times 

 the length, which remains actually about as in the somites of the middle region. 

 There are no sharply defined intersegmental furrows. The anal cirri are missing. 



The parapodia are long and relatively slender, excepting those of peri- 

 stomium and first metastomial somite much exceeding the width of the somites 

 to which attached. Each parapodium is widest a little distad of the base from 

 where in outUne as viewed from above it is at first of uniform width and then 

 from near the middle narrows to the distal end at which it is compressed to an 

 edge. Just proximad of the distal end it is raised into a thin ridge or plate 

 both above and below so that the outline as viewed from in front or behind 

 increases in height distad of the middle, again descending to the somewhat 

 pointed distal end. At the distal end it is produced into a subtriangular, dis- 

 tally somewhat rounded, presetal process or lip. There is no distinct post- 

 setal lip. There is no distinctly indicated notopodial lobe and there are no 

 notopodial setae. The notocirri are attached at the extreme bases of the para- 

 podia above. Their cirrophores are typically remarkably inflated above the 

 pedicel-like bases into subcylindrical bladder-like cushions or vesicles which 

 in the middle region of the body greatly exceed the adjacent elytrophores in 



