167 
Epidermis.… The epidermis is always very. well developed; the 
different cells: are very visible seen from the inner side and provided 
with small oblong rather irregular nuclei. Between these there are 
round cells with a large round nucleus; these are. probably glandular 
cells. At least in some specimens I saw clear vacuoles arranged 
around the nucleus. 
10. Sexual Organs. 
The females and the males are always, at least in my. spe- 
cimens, very eas to distinguish from each other. The female -pos- 
sesses a large ovipositor, and even if this is invaginated, it is 
recognisable by the. oviduts and eggs seen through the skin; .the 
male is always easily known by a complicated, system of accessory 
glands under the skin behind the genital opening. The. genital 
opening in both sexes is placed between the third pair of. coxae, 
and on each side there is placed an oblong movable, strongly raised 
body provided: with one slender pointed hair and five hairs. bear- 
ing spines (pl. V. fig. 8, 9,11.& 130; fig. 10). This body. is in 
reality a valve articulated to the. skin in front and at the sides, 
but with the hindmost and inner margin free, so that it may be 
raised and a glandular mass poured forth; the valve is closed by 
a separate retractor muscle (pl. V. fig. 13 mc). These. organs cor- 
respond perhaps to the so-called »copulative suckers". that are found 
in different forms in other Acari. 
The Male Organs (pl. VI fig. 2, 3, 4, 8, 9, 10, 16, 17, 18 & 19). 
The Testis.… The: most peculiar part of. the male organs is a 
complicated system of accessory glands. The testis and their ducts 
have been very difficult to examine, and I have been obliged to let 
important questions remain unsolved. Along the back of:the intestine. 
parallel with the excretory tubes (€) but more inwards the testes 
(H) are placed going from the anus to the foremost part of. the 
ventricle.. They form two bands, getting more and more narrow 
from behind and forwards and consisting of a large number of cells; 
