754 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [36] 



separates, by a sharp division, the muscular wall fro in the inner cavity 

 of the segment, in which lie the genital organs. This layer of circular 

 fibers spreads out into a thin sheet of fine fibers, at intervals, to form the 

 septum between two adjacent segments. The fibers of this partition are 

 transverse, and run in the direction of the longer diameter of the seg- 

 ment; that is, from margin to margin. This partition is confined to the 

 inner portion of the segment, and does not extend into the muscular walls. 

 Elsewhere iu the segment the inner space is crossed by fascicles of fine 

 fibers which pass from oue of the lateral muscular walls to the other 

 without interruption, except where displaced by the developing ova. 



Following are the measurements of a transverse section of a postero- 

 median segment : From margin to margin, 2.7 mm ; from side to side, .9 mm ; 

 thickness of muscular walls, .3 mm ; marginal diameter of inner cavity, 

 .2 mm 5 lateral diameter of same, .36 mm - 



Habitat. — Gadus morrhua, pyloric ca3ca, August 8, 1886, Grand Banks. 



Family II.— TETKABOTHRIID^ Diesing. 



Tetraphyllidce (in part) Van Beneden. 



Subfamily I. — Phyllobothrin^e Van Beneden. 



Anthobothrium Van Beneden. 



The generic characters are thus summarized by Diesing: Body elon- 

 gated, articulate, depressed. Supplemental disks (auxiliary acetabular 

 none. Head separated from the body by a neck. Bothria four, oppo- 

 site, entire or unilocular, cup-shaped or subglobose, affixed by a con- 

 tractile pedicel, highly versatile, unarmed. Genital apertures marginal. 



7. Anthobothrium laciniatum, spec, no v. 



[Plate in, Figs. 10-13, and Plate iv, Figs. 1-3.] 



Head with four bothria, pediceled, trumpet-shaped, but capable of 

 much diversity of form. Faces of bothria concave, with entire circular 

 margins, but often folded and otherwise distorted by contraction. The 

 head proper, exclusive of the bothria, is very small, often in the living 

 worm appearing to be separated by a slight constriction from the first 

 segment. Neck, in one variety, none, or very short ; in another, vari- 

 riable in length, but evident, cylindrical, or quadrate, and terminated 

 behind by four laciniae. First segments usually much broader than 

 long, rather quadrate, i. c, rectangular in cross-section, laciniate. In 

 some the slender laciniae of one segment overlap the succeeding seg- 

 ment, and are longer than the body of the segment. In other cases the 

 anterior part of the body is extremely attenuated, in which case the 

 anterior segments may be considerably longer than broad ; the lacinise 

 are then only about one-third the length of the segment proper. In yet 



