380 THE ANNELIDA POLYCHAETA. 



AuDouiNiA Quatrefages. 



Hist. nat. annelcs, 1865, 1, p. 459. 



AUDOUINIA FILIGERA NESOPHILA, SUbsp. nOV.^ 



Plate 70, fig. 5, 6. 



The general color of the body is a somewhat slaty black. The branchiae 

 are bright yellow. 



The body is moderately slender. It is conically pointed at both ends, but 

 the caudal end is somewhat more slenderly so. The middle two thirds or three 

 fourths of the length is nearly uniform in thickness. The total number of seti- 

 gerous somites is in the neighborhood of 390. The total length is 75 mm.; the 

 greatest width about 3.5 mm. 



The prostomium is subcorneal, flattened, with the anterior end bluntly 

 rounded. It is abruptly narrower than the peristomium. No eyes detected. 



The peristomium is longer than the prostomium in about ratio of three to 

 two. It is in outhne roughly trapeziform, with the lateral borders convex. The 

 dorsal surface is divided by transverse and cross sulci into a number of irregular 

 rounded tubercles or areas. It appears as usual to be formed by the fusion of 

 three primary somites. The length of prostomium and peristomium together 

 is dr. 1.1 mm.; the width at base dr. 1.8 mm. The border of the mouth is 

 radially wrinkled, as usual. 



The first setigerous somite, as usual, is longer than the second, those fol- 

 lowing reducing gradually and being very short. From the end of the anterior 

 fourth or fifth the segments increase somewhat in length, but remain of nearly 

 uniform length over the middle and posterior regions. At the middle of the 

 body the somites are sixteen or seventeen times wider than long. The somites 

 in general are thus very short and closely crowded. All are distinctly separated 

 from each other. Ventrally they show an indistinct division by transverse 

 suture into two very unequal parts, the caudal of these being the shorter. 



The branchiae in general are fine and cirriform, those of the anterior region 

 being but httle coarser than those of the posterior. The longest noted had a 

 length of 15 min., being thus four or five times the width of the body in the middle 

 region. The branchiae in the anterior region arise in contact with the dorsal 

 setigerous tubercle and farther back the point of insertion is but little removed 

 from it. The paired branchiae occur anteriorly on all setigerous somites except 

 apparently the first. The special branchiae occur on the seventh setigerous 



'j^ffos, island, and^c^iXos, loving. 



