NO. 225S TAENIOID CESTODES OF DOGS AND CATS— HALL. 47 



thin, delicate, and comparatively translucent (fig. 48). The genital 

 primordia appear in about the thirtieth segment, between 2 and 3 

 mm. back of the head, first as deeper staining areas in the median 

 line. These areas become angular, the legs of the angles forming the 

 genital canals. The primordium of the median stem of the uterus is 

 the next thing visible. Calcareous corpuscles are especially large 

 and abundant in the medullary portion of the head and the anterior 

 portion of the neck, where they are elliptical and about 13 by 8 [x 

 in diameter, but are elsewhere small, oval, about 4 or 5 jjl in length, 

 and, though numerous, are relatively inconspicuous. The longitu- 

 dinal excretory canals are quite distinct, the ventral canal situated 

 about 225 \). from the margin of the segment and the dorsal canal 

 lying lateral of this. The genital 

 papilla is fiat and inconspicuous, 

 an actual papilla formation being 

 lacking as a rule, but is readily 

 observed, owing to the translu- 

 cency of the segments. 



Male genitalia. — There are be- 

 tween 200 and 225 large, irregu- 

 larly spherical testes, confined 

 principally to the lateral portions 



\ 



'*Wj 



of the median field in the vicinity • J>v@,'® N>r^*t-v-- - % 



of the longitudinal excretory ; \\\W^M^f^J'^^^^0^'^'' f 



\' 



"" 'VT'- 



canals (fig. 49). There is a wide 



field about the median stem of 



the uterus which is free or com- \ \'\;%i^^"Jf^^:^i^^ 



paratively free from testes, only \ \ ;;f%:j.«tJ^'^%'' ' " 



an occasional tAvo or three oc- ^-::i^^. 



curring here. The field about the /*'■// ^'^'^ 



vas deferens and vagina is also ' fT^rjTj ' 



comparatively free from testes fig. 49— multiceps gaigeri. mature segment. 



ft ^ T , 1 • 1 From Hall, 1916a. 



tor some distance on each side. 



The testes press close to and even in contact Avith the lateral borders 

 of the ovaries and also extend to the vitellarium and between the 

 vitellarium and the ovaries. The vas deferens begins close to the 

 median stem of the uterus on the pore side and first extends at an 

 angle posteriorly and laterally. It is very much looped from its origin, 

 the loops extending Avidely along the longitudinal axis of the worm, 

 even across the vagina, and also back and forth along the general 

 path of the vas deferens, the loops being so numerous as to form a 

 dense wide structure. The cirrus pouch extends to the median border 

 of the ventral excretory canal. It is piriform to elongate elliptical 

 in shape, often with a concavity on the posterior side, toward the 

 vagina, and about 260 \i long by 100 to 125 [i. wide. 



