105 
their long axes directed parallel to 
and occupy almost the entire thick- 
ness of the inner parenchyma. The 
two dextral testes are in the pos- 
terior half, the other one in the 
anterior half of the proglottis. . 
The ms deferens (r. def.^ tig. 11 T) 
in its course to the genital pore 
lies toward the dorsal side of the 
segment; after passing the right 
hand testis it swells out into a large 
seinincd vesiclefes. sern. e-r. . tig. 11 i ) 
then somewhat reduced again in 
size describes one or two S -shaped 
loops, and enters the base of the 
cirrus pouch. 
The latter (c. tigs. 115, 117) 
is a powerfully developed club- 
shaped organ, which when straight 
lies entirely in the anterior half of 
the proglottis; it may be bent S-like 
and lie in the posterior half of the 
proglottis as well. It measures in 
length from 0.S2 to 1.2 mm. and 
<_5 
from 60 to 190/^ in width at differ- 
ent points. Externally the cirrus 
pouch (tig. 121) is supplied with a 
layer of longitudinal muscle lamella? 
(//0 />Z.) which has a maximal thick- 
ness of 50//. The lamella? become 
graduallv thinner toward the distal 
end of the cirrus pouch, and in its 
outer third are reduced to a very 
thin muscle layer. In relation to 
the muscle lamella? is a thick layer 
of myoblastic cells (///y. ). IVithin 
the cirrus pouch the vas deferens 
is again enlarged to iovrci'A serniaal 
vesicle which lies toward the dorsal 
side. The vas deferens, near the 
junction of the middle and outer 
thirds of the cirrus pouch, becomes 
reduced in size, turns mediad and. 
running along the ventral wall of 
the oouch again swells" out into 
transverse axis of the segment. 
Fig. 117. — Transverse seorion of proglottid of H. 
Janceolata: c. p., cirrus pouch; e:e. can., excre- 
tory canals; I. n., lateral longitudinal nerves: 
ov., ovary: rec. sem., receptaculum seminis; t., 
testis; ut., uterus; vag., vagina; v. def., vas 
deferens; v. ej., vas efferens; ves. sem. e:c., 
vesicula seminalis externa; res. sern. int., 
vesicula seminalis interna; y. g., yolk gland. 
Enlarged. (After WolfThtigel. 1900b, p. 51, fig. 2.) 
small spindle-shaped vesicle in 
