5 98 EEPORT OF COMMISSIONER OF FISH AND FISHERIES. 



meDce ou tlie twenty-sixth setigerous segment as minute papillse; on 

 the twenty-eighth they become prominent and acute-conical; farther 

 back they become long, lanceolate, thin, foliaceous, as long as the diame- 

 ter of the body. 



On the twenty- three anterior setigerous segments the " feet" are rep- 

 resented by two short, dense, fan-shaped fascicles of setae on each side- 

 On the twenty-fourth segment a small papilliform lobe, or ventral cirrus, 

 appears below the lower ramus, which rapidly becomes larger on the 

 succeeding segments, becoming quite conspicuous on the twenty-ninth 

 segment; at about the twenty-eighth it becomes broader, and divided 

 into three small lobes, the lowest broadest and thinnest, and a bilobed 

 setigerous lobe is developed. At the thirtieth the ventral lobe becomes 

 broader, somewhat foliaceous, with a rounded outline; farther back 

 this becomes still larger and more foliaceous, with a broadly-rounded 

 llexuoas outer border, and the upper branch of the setigerous lobe be- 

 comes an elongated ligulate process, directed upward, and similar in 

 form to the branchiae, though smaller and more slender, but the lower 

 branch remains small and rounded ; a small fascicle of long, slender 

 setae arises from between them. On the twenty-seventh segment an 

 upper cirrus appears on both the upper and lower rami, in the form of 

 a small papilla, which becomes somewhat elongated and tapering at the 

 twenty-ninth ; that of the lower ramus continues small throughout, and 

 much shorter than the setigerous or ventral lobes, but that of the upper 

 ramus becomes rapidly larger, longer, and more ligulate, corresponding 

 nearlj^ with the branchiae in size, form, and rate of increase. On the 

 middle and i30sterior regions the upper ramus consists of this long, 

 thin, lanceolate cirrus and a fascicle of long, slender setae, arising from 

 the anterior face of its base, and in length con siderably exceeding the 

 cirrus; the setae are pale yellow. Those of the upper ramus are short 

 anteriorly, and become decidedly longer at the twenty-eighth segment, 

 and on the thirty-second and subsequent segments they form a long, 

 divergent, fan-shaped fascicle; color, when living, ocher-yellow, orange- 

 yellow, to yellowish brown, generally brighter yellow posteriorly. Usu- 

 ally there are two rows of brown spots along the back, and posteriorly 

 there is ai dorsal red or reddish brown line; branchiae blood-red. 



Length of large specimens up to 375""" or more; breadth, 10"""; ordi- 

 nary specimens are about 300'""^ long and 7""" broad. Owing to the 

 facility with which it breaks up when disturbed, it is difficult to obtain 

 entire specimens of large size. 



Great Egg Harbor, New Jersey; New Haven; Wood's Hole; in sand, 

 at low-water. 



Antiiostoma fragile Verrill, sp. no v. (p. 344.) 



Body long and slender, composed of very numerous segments, very 

 fragile, and prone to divide spontaneously when disturbed ; thickest 

 and sub-cylindrical anteriorly, tapering rapidly to the head ; posterior part 



