452 
ADAM SEDGWICK. 
The segmentation stages were all drawn in the laboratory as 
I removed them from the uterus, and it is entirely owing to 
Mr. Wilson’s kindness that I have been able to obtain a per- 
manent and accurate record of tbe various stages of the living 
segmenting ovum. 
The Generative Organs. 
At the outset I must give a short description of the general 
arrangement of the generative organs. Their minute struc- 
ture I shall describe more fully when I come to their develop- 
ment. 
Male Organs. — The description given by Moseley 1 and by 
Balfour 2 is correct so far as the general arrangement is con- 
cerned, but a slight rectification is necessary in the significance 
to be attached to the various parts. The structures called testes 
by these authors (Balfour, loc. cit., PI. XX, fig. 43, te .) are ap- 
parently merely seminal vesicles, in which the spermatozoa de- 
velop and gain maturity. The true testes are the so-called 
prostates (Balfour, loc. cit., fig. 43, pr.), the lining cells of 
which fall into the cavity of tbe tube, pass into the swollen 
seminal vesicle, where they develop into spermatozoa. The 
spermatozoa, when ripe or nearly ripe, pass into the vasa 
deferentia, at the lower end of which they apparently become 
packed together in small masses, which become surrounded by 
a structureless coat, and are passed out as small, oval, white 
spermatophores. 
The male generative organs of Peripatus capensis con- 
sist, therefore, of a pair of blind tubes, which are separate in 
front, but united behind for a short distance to form a common 
terminal portion (Balfour, loc. cit., fig. 43, p), and at the front 
end of which are formed the mother-cells of the spermatozoa. 
The latter fall into the cavity of the tube, and gradually de- 
velop as they pass backwards towards the external orifice, the 
1 ‘Phil. Trans.,’ vol. 164. 
s This Journal, 1883. 
