200 RESEARCHES IN HEI.MINTHOLOGY AND PARASITOLOGY. 



being killed off, though the living birds infested, which were ob- 

 served, appeared not to be suffering in nutritive condition. The 

 species seems to be the 'T(enia microps, Diesing ; the same which 

 infests the Capercailzie, Tctrao urogallus, of Europe. Its charac- 

 ters are as follows : Head globose or oval, without rostelluni or 

 armature, and with a central fovea at the vertex. The four bothria 

 spherical or oval. Neck long, variably narrower than or as wide 

 as the head. Anterior segments, where distinct, about three times 

 the breadth of the length ; subsequently seven or eight times the 

 breadth of the length ; afterwards again about three times the 

 breadth of the length ; then nearly square ; next longer than broad ; 

 and finally two or three times the length of the breadth. Segments 

 mostly flat, or narrowly elliptical in section, but finally nearly as 

 thick as wide, so as to be oval or nearly circular in section. Genital 

 apertures marginal, alternating, most distinct in the middle segments. 

 Ova, in the terminal segments, oval, colorless, with an embryo pro- 

 vided with three pair of spines. 



Length 9 inches, greatest width 2^^ lines. Measurements of sev- 

 eral individuals were as follows : 



No. I. Length, 28 centimeters. Head, 0.375 mm. long, 0.45 

 broad. Bothria, 0.225 by 0.25. Neck, 2 mm. long, 0.25 where 

 narrowest. Anterior segments, 0.125 to 0.175, .75 to i mm. broad; 

 middle segments, 1.5 long, 4.5 broad; terminal segments, 2 mm. 

 long, I broad and thick. 



No. 2. Length, 11 centimeters. Terminal segments, i mm. long, 

 4 broad. 



No. 3. Length, 17 cm. Head as in No. i. Neck. 2.5 mm. long. 

 Anterior segments, 0.125 nim. long, 0.3 broad, and then 0.45 broad. 

 One-third the length behind, i mm. long, 2.25 broad ; terminal 

 segments, 3 long by i to 1.25 broad. 



No. 4. Length, 15 cm. Terminal segments, 1.5 mm. long, 4.5 

 broad. 



No. 5. Length, 22 cm. Terminal segments, 1.5 mm. long, 4 

 broad. 



No. 6. Length, 16 cm. Middle segments, i long, 2.5 broad ; 

 terminal segments, 2 long, 1.5 broad, i thick. 



No. 7. Length, 25 cm. Middle segments, i mm. long, 5 broad ; 

 at posterior fourth, 2 long, 3 broad ; terminal segments, 3 long, 2 

 broad, 1.5 thick. 



No. 8. Terminal segments 5 mm. long, 1.5 wide, i thick. 



No, 9. Terminal segments 3.3 mm. long, 2 wide and thick. Ova 

 0.12 mm. long, 0.08 broad. 



