592 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



the body composed of numerous short segments, on which the feet are 

 furnished with lamelliform appendages. 



This remarkable annelid bears some resemblance, in the structure of 

 the body and '' feet," to Reteronereis, and there is probably another form 

 to which it bears the same relation that Heieronereis bears to Nereis ; but 

 the structure of the head is very unlike that of any known genus, and, 

 indeed, would not allow it to be placed in the family of Nereidce without 

 modifying the family-characters-. There are are no large palpi, corre- 

 spondiug to those of Nereis, aud nothing to represent them, unless two 

 small lobes close to the mouth be considered rudimentary j^alpi. 



Nectonereis MEaALOPS Yerrill, sp. nov. Plate XII, figs. 02, 63. (p. 

 ■440.) 



Body slender, consisting of two parts; the anterior i>ortion, contain- 

 ing fourteen setigerous segments, is broadest in the middle, tapering 

 both ways, and separated from the posterior portion by a distinct con- 

 striction 5 the posterior portion is much longer and more slender, taper 

 ing gradually to the end, and consists of very numerous short segments, 

 which are furnished with complex lateral appendages, with thin lamelloe 

 and compound bladed seta3. Head broad oval, somewhat convex, and 

 very smooth above ; the lateral margins a little convex ; the front 

 obtusely rounded. Eyes very large, convex ; the anterior ones largest, 

 lateral and partially dorsal, oval ; in contact with the posterior ones, 

 which are somewhat smaller and more dorsal. Two small decurved 

 antenucT, with swollen bases, are on the ventral side of the head ; two 

 small, rounded processes in front of the mouth. Tentacular cirri 

 slender, the upper pair much the longest ; the rather short lower pair 

 arising near the mouth,- the two intermediate pairs arise behind and 

 close to the anterior eyes ; all are slightly annulated. The ''feet'' on the 

 first seven segments have a large dorsal cirrus, increasing in length 

 from the first to the seventh, narrow at base, swollen and gibbous 

 toward the end, with a slender, oblique, terminal portion; on the seven 

 following segments the dorsal cirri are smaller, slender, tapering; 

 the ventral cirri are small, with swollen bases on the first five seg- 

 ments, slender and tapering on the rest ; the intermediate lobes of the 

 feet are small and rounded, but more elongated on the first five seg- 

 ments. Setiie of difterent forms, many of them with a slender, often 

 curved, acute terminal piece. 



The lateral appendages of the posterior region have, on the upper 

 ramus, a long, slender dorsal cirrus, strongly creuulate-lobed on the 

 lower side; a small, rounded lamelliform process above its base; and a 

 long, lanceolate process arising just below it, and in length equaling" 

 the cirrus ; an ovate setigerous lobe, bearing a broad fan-shaped fascicle 

 of compound seta>, extending about to the end of the dorsal cirrus : 

 and a lower ovate-lanceolate lamelliform process, with the base expanded 

 aud extending backward, the tii) reaching to about the outer third of 



