LOPADORRHYNCHUS NANS. 117 



The tentacular cirri are six in number. The first dorsal pair are stout and 

 pointed, and reach to the second setigerous somite; the ceratophore is distinct, 

 a little longer than thick, and thicker than the style. At the base of each is 

 inserted a very much smaller but distinctly developed ventral cirrus. The third 

 tentacular cirri are similar in form and size to those of first dorsal pair. Ven- 

 trally the division to which the last tentacular cirri pertain is single, immediately 

 caudad of the mouth, presenting a quadrate area which projects caudad over 

 the succeeding somite, the caudal edge very slightly obtusely angular; the 

 anterior border of this area, or lower Up, limiting the mouth behind is nearly 

 straight, being usually scarcely incurved. 



The metastomial somites in general are very flat ventrally and but moder- 

 ately convex dorsally, the body as a whole appearing depressed. All are strictly 

 simple. The first one has the ventral region projecting back a little distance 

 over the next somite, the projecting portion being widely concavely excavated 

 and thus appearing as two well-separated, connected, triangular projections. 

 On the second somite there is a similar ventral extension caudad; but it is 

 shorter and wider, and the concave excavation is but sUght, the caudal margin 

 appearing merely gently incurved from side to side. The third and succeeding 

 somites are normal, presenting no extension of the venter whatsoever. The 

 somites, while varying in width as previously indicated, remain of nearly con- 

 stant actual length. In the widest part of the body the somites are about three 

 times wider than long. The pygidium is a short, blunt, mesally slightly indented 

 somite from which the cirri in the type have been lost. 



The first three neuropodia are short, deep dorsoventrally but less thick at 

 base anteroposteriorly, and distally becoming decidedly thinner and more 

 flattened. In caudal or anterior view the margin is distally rounded, the ventral 

 slanting portion being more oblique and less curved. They are somewhat 

 constricted at the base. At the tip there is a slender and very short, translucent 

 postsetal process with a low, membranous extension ventrad and a wider, thin 

 and foHaceous but equally short, presetal Up. The fourth neuropodium is con- 

 siderably longer, and the succeeding few more gradually increase in length. 

 In these neuropodia caudad of the third the flattening distally is more pro- 

 nounced; the presetal lip is broader and higher, less pointed but still obtusely 

 angular, next becoming obliquely truncate and then convexly rounded, but in 

 the posterior region again becoming pointed and increasing in height, while the 

 postsetal lip disappears as such. The first three neuropodia at first sight seem 

 to bear no ventral cirri, unless, as I am inclined to believe, the postsetal process 



