142 
Transactions of the Societtj. 
IV. — On the Variations of the Female Reproductive Organs, 
especially the Vestibule, in different species of TJropoda, 
By Albert D. Michael, F.L.S., F.Z.S., F.E.M.S., &c. 
{Read 19^7^ March, 1890.) 
Plate IV. 
In January 1889 I read, before this Society, a paper upon the internal 
anatomy of Uropoda Krameri* In that paper I described, inter 
alia, the female reproductive system, which on the whole agreed fairly 
well with that of the Oribatidse ; but in which the long ovipositor 
EXPLANATION OF PLATE IV. 
ov, ovary, od, oviducts, e, egg. va, vagina, n, neck of same. terminal part 
gathered round the heel of the perigynum. pg, perigynnm. ves, folded and flexible 
membrane attached round the edge of the perigynum above, and round the edge of 
the genital aperture below; this membrane and the perigynum form the walls of 
tlie vestibule.'’ gp, genital plate (epigynum). gp^, thin projecting portion at the 
anterior end of same. c7d, chitinous strengthening-pieces along the lateral edge 
of the perigynum. rs, receptaculum seminis. ag, accessory glands, occlusor 
muscles of genital plate, tendinous attachment of same. levator muscles of 
the perigynum. depressor muscles of the lower edge of the neck of the vagina. 
i^, tendinous attachment of same, vp, portions of the chitinous ventral plate. 
Lettering applicable only to the figures of Uropoda ovalis. — m"*, retractor muscles 
of receptaculum seminis. /, fold of ves. fr, fringe round edge of perigynum ou 
the ventral side. cJd, chitinous strengthening-piece round the heel of the peri- 
gvnum. CO, collar of clear chitiu attached to same, chitinous strengthening- 
})iece partly round the edge of the receptaculum seminis. gm, membranous spatulate 
piece lying within the hollow of the genital plate. 
Lettering applicable only to figures of Uropoda vegetans. — si, sigmoid piece. 
Fig. 1. — Uropoda ovalis 'K.och. $. Whole genital system seen from the dorsal surface 
(above), X 65. 
„ 2. — Ditto. Anterior portion of same, side view, x 100. 
3. — Ditto. Perigynum and surrounding parts, and neck of the vagina, seen 
from the dorsal snrface (above), x 150. 
,, 4. — Ditto. Perigynum and portion of the other parts of the vestibule seen 
from the ventral surface (below), x 150. 
5. — Ditto. Side view of the perigynum, vagina. &c. ; the accessory glands, 
fringe, and membranous poition of the vestibule have been removed in 
order to show the attachment of the muscle and tendon rrd U to the 
lower edge of the neck of the vagina, which is drawn backward, x 150. 
0. — Ditto. Opening of the neck of the vagina, seen from the anterior end of 
the creature, showing the insertion of the heel of the perigynum into 
the opening, x 200. 
7. — Ditto. Perigynum detached ; three-quarter view to show the shape, x 100. 
8. — Ditto. Eeceptaculum seminis from below, x 150. 
’, 9. — Ditto. Genital plate (epigynum), x 60. 
10. — Ditto. Thin projecting end of same, x 150. 
„ 11. — Ditto. Sagittal section, nearly median, X 60. mo, mouth-aperture, co, oeso- 
phagus. V, ventriculus. c, colon, r, rectum (cloacal). a, anus, mg, por- 
tions of the Mal{)ighian vessels (cut through by the section), dp, dorsal 
chitinous plate with lining membrane, ep, epistome joined to dorsal 
pl.te by a median chitinous lamina, ot, chitinous walls of the oral 
This Journal, 1889, pp. 1-15. 
