672 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



Semiscolex grandis Verrill, sp. nor. 



Body very large, broad, stout, with about 90 well marked annulations, 

 foriniug crenulatious aloug the margius; length, in full extension, 10 to 12 

 inches or more; greatest breadth, 1 to 1.25 inches. Head somewhat pro- 

 longed and tapered, composed of several distinct annulations. Ocelli, 

 10 : the first pair near together on the first annulus of the head ; the 

 second pair on the second annulus; the third pair on the third annulus; 

 the fourth pair on the fifth annulus; and the fifth pair on the eighth an- 

 nulus. Upper lip divided beneath into two median and two lateral areas 

 by three deep, triangular fossre ; each of these areas is subdivided by 

 numerous longitudinal and transverse wrinkles, the small interspaces 

 being rather smooth ; the lip is separated from the opening of the oeso- 

 phagus by a deep transverse groove, bordered below by a membrane, 

 which rises into three tran verse folds or lobes, but these are often rather 

 indistinct in preserved specimens. Oesophagus relatively small and 

 short, with about twelve unequal plications or folds, some of which are 

 often indistinct, or united anteriorly, and sometimes with additional 

 small ones intercalated between the larger ones posteriorly. No distinct 

 maxilliB could be detected. Male orifice situated between the twenty- 

 fourth and twenty-fifth annuli behind the mouth; female orifice in the 

 thirtieth annulus. The male orifice is in a small, circular pit, from which, 

 in one specimen, a long, filiform, intromittent organ is extended to a dis- 

 tance equal to half the breadth of the body, or about 0.5 of an inch, 

 (11™™.) The female orifice is transversely elliptical, with slightly raised 

 and rugose margins. Acetabulum small and deep, projecting less than 

 half its diameter beyond the end of the body. Anal orifice large, sur- 

 rounded by numerous convergent plicae. 



Color dusky brown above, somewhat paler beneath, sometimes with a 

 few rather large, roundish, but irregular, distantly scattered dark spots 

 on the back, and often with two or three beneath ; sometimes nearly uni- 

 form slate-brown, with only a few, small, remote blackish spots. 



Var. h, maculatus. — Form and size as in the preceding variety. Color 

 above olive green or yellowish green, thickly spotted with irregular angu- 

 lar, more or less confluent, blotches of blackish. The folds of the oesoph- 

 agus, in the single specimen examined, consist of three broad ones, im- 

 perfectly and rather indistinctly divided into three subplicaj; alternating 

 with the three broad folds were three narrow and inconspicuous ones. 



Var. a, West River, New Haven, Conn. — A. E, Verrill ; Lake Huion, 

 at Au Sable, Michigan. — J. W. Miluer. 



Var. h, Madeline Island, Lake Superior — J. W. Milner. 



Hexabdella Verrill. 



Op. cit., vol. iii, p. 136, 1872, 

 Body depressed posteriorly. Cephalic lobe prolonged, composed of 

 four segments, with three longitudinal folds beneath, followed by three 

 transverse fleshy lobes, or folds ; below these, the oesophagus is fur- 



