bo 
164 
MR. H. N. MOSELEY ON THE ANATOMY AND 
Fig. 5. 
. 7. 
. 8 . 
immediately above the junction with the testis. The contents of the testis- 
cavity divide themselves into two regions — an outer, where the formation of 
the larger spermatic cells takes place, and an inner, where the cells ripen and 
the spermatozoa are formed. The tails of the spermatozoa are seen turned 
towards the outlet. 
E. External layer of capsule. 
l. Internal ditto. 
D. Duct. 
G. External region with smaller cells. 
C. Internal with larger cells and spermatozoa in process of formation. 
m. Longitudinal muscular fibres of the body. 
Testis of same animal, which has discharged its contents and collapsed, lowly 
magnified. An internal membrane has parted from the capsule, and is seen 
folded up in the anterior. 
Spermatozoa of E. Tliwaitesii in process of development. 
Sections of vas deferens of Eipalium Diana , highly magnified. 
Longitudinal section in the plane of the body of the ovary of Eipalium Diana, 
from various chromic acid and alcohol preparations. The ovary, which is 
thus seen in section, has an oval outline, and is crowded with ova in various 
stages of development. The oviduct, with its funnel-shaped expansion and 
ciliated epithelium, is seen passing up on the right-hand side of the ovary in 
the drawing. The exact manner of its connexion with the ovary was not 
ascertained in this species, but is probably similar to that in Ehynchodemus 
(see fig. 13). In Bipalium Diana the duct was not traced further than is 
represented in the drawing It enters on the most external side of the ovary — 
that is, the side which is furthest from the median line of the body. Imme- 
diately exteriorly to the oviduct is seen the small yelk-gland attached to the 
ovary by a pedicle, which is probably its duct. This gland was present in the 
condition here represented only in one specimen examined ; in the remainder 
it was quite rudimentary. In the ovary there is a special aggregation of 
immature ova at the summit. Some stroma-fibres with fusiform cells are 
seen to pass between the more mature ova. The organ has a compact inner 
tunic, which is succeeded externally by a loose fibrous investment. The whole 
lies imbedded between the internal longitudinal muscles, some fibres of which 
are seen on each side of it in the drawing. 
a. Outer loose fibrous investment of ovary. 
1). Inner denser ditto. 
c. Immature ovgi. 
d. Mature ova. 
e. Stroma-cells. 
f. Longitudinal muscular fibres. 
