724 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [6] 



There is danger of some confusion in the use of the terms marginal 

 and lateral in the description of this worm, arising from the fact that 

 what one naturally calls the margin of the head is continuous with the 

 lateral face of the body; in a brief description of the worm, therefore, 

 one should say bothria lateral, if by bothria the deep fossae are meant. 



The posterior segments are slightly irregular; in one case two seg- 

 ments were fused into one and the last segment was somewhat distorted. 



The following measurements were taken from the longest specimen 

 after it had lain for some time in alcohol. Length of strobile 720 mm ; 

 length of head4 mm ; breadth of he,ad at base2 nmi , middle 2.5 mm , apex I mm ; 

 thickness of head 1.5 mm ; diameter of neck l mm . The diameter of the 

 neck, or, more properly speaking, of the body immediately behind the 

 head, is a trifle greater when measured in a line corresponding to the 

 breadth of the head than it is on a line corresponding to the thickness 

 of the head. 



In the alcoholic specimens the shape of the body differs very little 

 from that of the living worm. It still has the same uniformity of breadth 

 throughout. There are, however, some differences in the head which are 

 worthy of mention. The head of the alcoholic specimen is shorter, 

 thicker, and more bluntly pointed than that of the living specimen. 

 The apex of the head is almost truncate. The lips of the fossae are 

 more or less crimped and folded and the fossae are somewhat gaping, 

 while the broad lobes are deeply furrowed. These furrows are, in 

 the main, longitudinal. 



The median lateral furrows of the body are, in the alcoholic speci- 

 mens, very strongly marked. Near the head each median furrow ap- 

 pears to turn to one side in order to meet the fossa of the head, in which 

 it terminates. The true nature of this apparent twist in the anterior 

 part of the body is made evident by transverse sections of the head and 

 anterior segments as described further on. While in the living worm 

 the anterior segments are very indistinct, in the alcoholic specimens 

 they are tolerably distinct and can be traced almost to the head. 

 Near the head they are about .17 mm in length and l mm in breadth. At 

 a distance of 15 mm from the head the length is ,22 mm ; breadth 1.2 mm ; 

 thickness .84 mm . Two hundred millimeters back of the head the seg- 

 ments are ,36 mm longf, 1 .8 mm broad and .8 mm thick. At a distance of 330 mm 

 from the head the segments are .8 mm long, 1.8 mm broad and 6 mm thick. 

 Near the posterior end of the longest specimen, the length of the seg- 

 ment is 1.9 mm , breadth 1.4 nim , thickness .5 mm . 



After staining with carmine, transverse sections of the head were 

 made in order to ascertain, if possible, the nature of the fossae as coin- 

 pared with the cupping disks of such a species as D. microcephalum. 

 The sections at the apex of the head prove the fossae to be true bothria, 

 Fig. 0. In these sections there is a nearly square central part meas- 

 uring .22 and ,3 mm in its two diameters, with the crescent-shaped sec- 

 tions of the apices of the bothria lying at the two longer sides. In the 



