96 
meter. 
Like the cysticercoid of SymenoUjjts nano., it has a body and 
a tail, and may therefore be termed 
a cercocystis. The tail is rather 
long’, two or three times the length 
of the body (fig. 102). As in the 
case also of H. nana (see p. 10) the 
body is a gastrula-like structure, 
with an anterior opening and a sec- 
ondary caAuty formed by inyaglna- 
tion. Likewise, a yery thin pri- 
mary cayity separates the outer and 
the inner wall. The two walls are 
highly differentiated (figs. 103. 101). 
The outer consists, proceeding in 
the order from without inward, of 
a thick cuticula striated radially, a 
layer of fusiform, somewhat cylin- 
drical cells, a layer of circular fibers 
(muscular ?), a layer of cells much 
elongated longitudinally, and final- 
ly a lamellar layer. The second 
layer is not complete, but forms 
two longitudinal bands on opposite 
sides of the body. In cross section 
the body is seen to be rather oyal , 
with these two bands of cells, cut across, corresponding to the poles of 
the major axis of the ellipse (fig. 1< T). The inner wall is composed of 
a layer of reticular connective 
tissue, rich in cells and calcare- 
ous corpuscles, and lined with 
cuticula. The relations of the 
scolex are the same as in the cer- 
cocystis of IL nana (see p. 40); 
that is. it lies within the second 
cavity, and is attached behind to 
the inner wall by a peduncle, 
which in this case, howeyer. is 
thicker and shorter than in II. 
nana. The primitiye cayity is 
well defined in good prepara- 
tions: it does not extend into the 
tail. The anterior opening of 
the secondary cayity is yery nar- 
row and deep. The four excretory yessels form horseshoe-like loops 
in the scolex in relation with the inner wall (fig. 106). 
Fig. 103.— Longitudinal section of cercocystis of 
K. diminuta: 1. ext., external wall; 1. int.. inter- 
nal wall; pr. cav., primary cavity; sec. car.. 
secondary earnty. Enlarged. (After Grassi A 
Rovelli, 1892a. pi. 4. fig. 3. i 
pr.ca\/. 
Fig. 104. — Cross section of cercocystis of H. diminuta: 
l.ext.. external wall: 1. int., internal wall; pr.cav., 
primary cavity; sco., scolex; sec. cat., secondary 
cavity. Enlarged. (After Grassi & Rovelli, 1892a, 
pi. 4. fig. 2.) 
