1 86 RESEARCHES IN HELMINTHOLOGY AND PARASITOLOGY. 



together with fragments of others, and was labeled " Passed from 

 a Tront caught in the river August 14, 1882." The worms belong 

 to a species of Bot/iriocep/iahis or Dihothrium, apparently different 

 from either the D. i}ifundibuUfori)ic or D. proboscidcion , found in 

 Sa/mo sa/v(ii?ii(s, S. sa/ar, S. trutta, and other fishes of the kind. 

 The specimens are all mature, the segments from near the head 

 throughout being distended with brownish eggs. The characters 

 of the worm are as follows : Body linear, bandlike, widest just be- 

 hind the head and gradually narrowing to the posterior extremity, 

 thickened along the middle and to a less degree along the lateral 

 borders, which are narrowly obtuse at the free edge, apparently 

 continuous, but irregularly crenulate ; the broad surfaces trans- 

 versely wrinkled, with the lateral borders defined from the middle 

 by longitudinal striae ; anterior extremity wider and transversel}- 

 convex ; posterior extremity obtusely rounded. Head small, oval, 

 equitant across the anterior border of the body, with an oval bothria 

 fore and aft, directed obliquely from the broad surfaces of the body. 

 No distinct neck. vSegments of the body commencing immediately 

 after the head, wider than long, indistinctly defined at the lateral 

 margins and most marked transver-sel}' along the middle of the 

 body, becoming narrower and slightly longer at the po.sterior part 

 of the latter, fertile throughout and furnished on one side of the 

 body, in the median line, with a prominent penal papilla and just 

 behind with a genital pore. Animal whitish, with a median chain 

 of brownish spots, due to the ova-distended uteri. 



In a specimen of eight inches in length the anterior extremity of 

 the bod)' is 3 mm. wide, at the middle 2 mm., and at the posterior 

 extremity 1.5 mm. The head measures 0.16 mm. transversely and 

 0.18 mm. deep or long on the broad aspect of the worm. The seg- 

 ments generally measure about 0.625 mm. long. The ova are 

 brownish, oval, and 0.04 mm. long by 0.024 broad. 



The second vial contains a single worm and is labeled "Taken 

 from the intestine of a Trout Aug. 29, 1882." This \vorm I sus- 

 pect to represent an immature stage of the former. It is 30 mm. 

 long and in shape resembles the fluke- worm or a leech. It is elon- 

 gated elliptical, flat, widest in front, with the lateral margins appar- 

 ently entire, the broad surfaces transversely striated and longitudi- 

 nally divided into three bands, with the median band indistinctly 

 divided into segments, on one surface in the median line provided 

 each with a minute pore. Head oval, situated fore and aft across 

 the anterior transversely convex border of the body, with a minute 

 oval bothria fore and aft. Caudal extremity narrowest transversely 



