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DESCRIPTION OF PERIPATUS OVIPARVS, 
ovary, to which they are attached. Near to its point of origin each 
bears an oval receptaculum seminis with two ducts. It is very 
important to observe that each oviduct is divided into three parts. 
All three parts are narrow except where swollen by the contained 
eggs. The first is very short and extends from the point of 
attachment to the ovary to about the level of the receptaculum; 
its wall its greatly folded and provided with little excrescences on 
the side opposite to the receptaculum. The middle and last 
portions of the oviduct are of about equal length. The middle 
portion is very thick- walled and apparently glandular. The last 
portion has very thin, transparent, membranous walls. At their 
hinder ends the oviducts unite in a thick-walled triangular sac, 
whose posterior angle is continued into the ovipositor. 
I have found eggs in both the middle and last portions of the 
oviduct, but much more abundantly in the last. Their number 
varies greatly. In one specimen, for example, there were three 
eggs in each oviduct; in a second there were seven in one and six 
in the other; in a third there were eight in one and nine in the 
other. 
The eggs at the time of laying show no appearance of embryos 
within them, but each consists of a quantity of milky fluid, con- 
taining numerous yolk granules, enclosed in a very thick, tough, 
but rather soft envelope of a pale yellow colour and beautifully 
sculptured on the outside. The sculpturing consists of little 
crumpled papillae, somewhat resembling worm-casts, arranged at 
fairly regular intervals over the surface, and with much finer 
meandering ridges occupying the spaces between them. The eggs 
are oval in shape and measure about 1 '9 by 1 *5 mm. 
A careful re-investigation of my material has led me to the 
following conclusions with regard to the egg-envelope. The 
envelope really consists of three membranes. (1) A very thin 
transparent membrane immediately surrounding the yolk and 
probably to be regarded as a vitelline membrane. (2) A Yery 
thick membrane which is apparently formed as a secretion in the 
thick-walled part of the oviduct. In sections of a female contain- 
ing eggs in the oviduct this membrane is very clearly shown, and 
