r 
118 
where the sphincter issituated, 
it becomes very low. Imme- 
diately thereafter the epith- 
elium of the vagina increases 
so much in thickness that it 
may exceed the epithelium 
of the body to quite a con- 
siderable degree. The shell 
giands are spread out over the 
post-pharyngeal section of the 
body and empty as compact 
masses into the distended part 
of the vagina. As text-figure 
13 shows, they do not in this 
case reach the narrowing of 
the sphincter. The great mass 
of Shell giands is certainly 
connected with the large pro- 
duction of eggs. The wide 
Shell giand duet that comprises 
the longest part of the vagina 
indicates that in all probability 
more than one egg is enclosed 
in each egg*capsule. Such a 
condition is not unusual in 
Planoceridae, but is unknown 
in Stylochidae. On account of 
the organization of the vagina, 
a similar feature cannot be 
expected in the genus Stylo- 
chus, and my observations of 
the deposit of the eggs in a 
couple of Stylochus-species 
confirm this opinion. 
The glandless pars interna 
vaginae has the ordinary dia¬ 
meter and comprises the 
curving tube and the inner 
Texl-lig. 12. Leptostylochu.s elongatiis. Sagillal section through the genital apparatus. 60 x. de, ductus ejaculatorius; i.br, intestinal branch; 
Lv., Lang’s glandular vesicle; mi, main intestine; imi, entr.nnce of the uleiine canals into the unpaired uterine caiial; p, penis; 
php, pharyngeal chamber; pr, prostatic vesicte; s, shell giands; sph, muscle sphincter in pars interna vaginae. 
