780 
ME. H. N. MOSELEY ON THE STEHCTUEE AND 
Polygonal flat endothelium lining the ejaculatory sac of the slime-gland. Length 
of one of the longest cells - 06 millim. 
Structure of one of the ultimate ramifications of the slime-gland. Actual dia- 
meter of the tube ‘2 millim. 
Muscular fibres. 
a. Fibre in state of contraction, which has taken a somewhat spiral form. 
The shading gives somewhat the appearance of transverse striation. 
b. Portion of a fibre as seen under Hartnack’s No. 10, ocular 3. 
Portion of an embryo Peripatus in the condition seen in Plate LXXY. fig. 5, 
viewed in optical section to show the cell arrangement. The figure is taken 
from the hinder portion of the body, and represents one of the undulations 
of the lateral margin constituting the commencement of a member. 
a. External or epidermic layer. 
b. Middle layer. 
c. Dark mass of pigmented granules and oil-globules, out of which is to 
be formed the intestine. 
The middle layer is reflected over the intestine, which projects outwards to 
meet the body-wall in the interspaces between the members. 
PLATE LXXIV. 
Fig. 1. a. Ovary, oviducts, and commencement of uterus. The oviduct, as represented, 
is somewhat too short. Actual diameter of the ovarian ova T75 millim. 
The ovary is divided by a median longitudinal partition into two sacs. The 
dark longitudinal masses within these sacs are composed of felted spermatozoa. 
Other groups of spermatozoa are seen at the margins of the ovary in relation 
with the ova. The oviducts at a short distance from the ovary are well sup- 
plied with tracheae, which are, however, wanting on the ovary itself. On the 
left in the commencing uterus is seen a developing ovum ; its peculiar shape 
is believed to be due to partial collapse. 
b , c, d. Successive stages in the development of the ovum from a female speci- 
men the ovary of which was not yet ripe and contained no spermatozoa, and 
in which there were no embryos in the uterus. 
Figs. 2, 3. Cells from the testis of a male specimen, as seen in the fresh state, shawing 
the mode of development of the spermatozoa. 
Fig. 4. Further development of the spermatozoa. 
a,b. Vesicles of evolution, with the heads of the spermatozoa coiled within 
them and the long tails projecting freely. Each spermatozoon has its 
nucleus attached. 
c, d , e. Spermatozoa freed from the vesicle of evolution, but with the nucleus 
still attached. A slightly granular substance is visible, in most cases inter- 
vening between the nucleus and edges of the loop in which it lies. 
Fig. 6. 
Fig. 7. 
Fig. 8. 
Fig. 9. 
