Annelida Cbjeiopoda of New Jersey. 113 



On the posterior feet (fig. 29), the dorsal cirrus arises from the base of the 

 upper lunula; the remaining (posterior) lip of the upper ramus becomes deli- 

 cate, conical, reaching beyond the lingula. 



The anal segment (fig. 30) has a slightly crenulated margin ; its cirri are 

 delicate, their length more than double that of the longest tentacular cirrus. 



Setae of two kinds ; one, with long narrow appendix (fig. 31), one edge mi- 

 nutely denticulated ; the other (fig. 32) with short appendix, one margin thick- 

 ened and rounded, the opposite margin very thin, somewhat coarsely 

 denticulated ; those of the second form are found only in the lower bundle of 

 the ventral rami, after the first twenty to thirty segments, from four to six in 

 each bundle, always accompanied by some of the first form. 



Color, light flesh-color to reddish-brown ; dorsal cirri and superior lingulae 

 pure gleaming white, other parts of the feet also white ; head, especially its pos- 

 terior half, usually darker than the body. 



Body elongate, widest at the eighth segment, diminishing rapidly forward, 

 uniformly but very gradually backward. 



This species forms a tough membraneous tube, in color dark reddish-brown, 

 fitting the body very closely. 



Length of one specimen (140 segments) 60 mm ; width with feet 4 mm ; without 

 feet, 2 mm ; length of a larger specimen, 75 mm ; width with feet, 5 mm . 



Two specimens kept in well-water, not at all brackish, for forty-eight hours, 

 seemed to be in good condition ; while specimens of Nereis lirnbata Ehlers 

 treated in the same way stopped all movements in thirty minutes, and in an 

 hour the blood ceased to circulate ; the latter were taken at a higher station 

 than that in which the former lived, and where they must often have been ex- 

 posed to the action of brackish water. 



The only place in which this species was found was a few rods above the old 

 wharf, in front of the hotel at Beesley's Point, in coarse sand and gravel, at 

 about half-tide. We looked for them carefully in many other places, where the 

 conditions seemed to be the same, but without success. 



Sexual Forms. 



Many males and females, apparently adult, were taken, in which no structural 

 changes had occurred except that the eyes had become a little larger ; the ante- 

 rior pair crescentic ; the posterior oval ; the body and feet being swollen by the 

 contained sexual products. 



The color of the female was unchanged ; immature males were bright green ; 

 adult males greenish white. 



This species was first found by Mr. C. L. Culver, at Beaufort, N. C, in the 

 summer of 1877. Mr. Culver was at that time a student in Union College, and 

 attached to the usual summer zoological expedition of the college. He brought 

 in two specimens with a lot of Nereis limbata Ehlers, taken at low water. 

 The exact station was not known, and thoug i we searched diligently and fre- 

 quently for additional specimens, none were found. 



Nereis tridentata. n. sp. 



PLATE IV, FIGS. 33-40. 



Head (fig. 33) deeply emarginate in front, and with a well defined depression 

 carried back to the middle line ; behind the middle line the sides are convex ; 



