XVIII REPRODUCTION 461 
alimentary canal, which has been observed to be most marked 
during the more quiescent stages of the life-history. 
The internal reproductive organs have the ringed arrangement 
generally observed in the Arachnida. The two testes, which are 
sometimes bi-lobed, are connected by a median structure which 
may serve as a vesicula seminalis, and there are two vasa deferentia 
which proceed to the intromittent organ, which is sometimes situ- 
ated quite in the anterior part of the ventral surface, but at others 
towards its centre. The male Mite is often provided with a pair 
of suckers towards the posterior end of the abdomen, and some- 
times accessory clasping organs are present. 
In some Mites there is no intromittent organ, and Michael ' 
has described some remarkable cases in which the chelicerae are 
used in the fertilisation of the female, a spermatophore, or bag 
containing spermatozoa, being removed by them from the male 
opening and deposited in that of the female. The most remark- 
able instance is that of Gamasus terribilis, the movable joint of 
whose chelicera is perforated by a foramen through which the 
spermatophore is, so to speak, blown and carried as a_ bi-lobed 
bag, united by the narrow stalk which passes through the 
foramen, to the female aperture. 
The ovaries are fused in the middle line, and connected by 
oviducts with the tube (vagina or uterus) which passes to the 
exterior. There is often an ovipositor. 
Professor Gené of Turin” described, in 1844, some remark- 
able phenomena in connection with the reproduction of Ticks. 
The male Zzodes introduced his rostrum into the female aperture, 
two small white fusiform bodies emerging right and left from 
the labium at the moment of introduction. On retraction they 
had disappeared. When the female laid eggs, a bi-lobed vesicle 
was protruded from beneath the anterior border of the scutum 
and grasped the egg delivered to it by the ovipositor, appearing to 
manipulate it for some minutes. Then the vesicle was withdrawn, 
and the ego was left on the rostrum, and deposited by it in front 
of the animal. When the vesicle was punctured, and so rendered 
useless, the unmanipulated eggs quickly shrivelled and dried up. 
Lounsbury’® has recently confirmed Professor Gene’s observation 
1 Tr. Linn. Soc. (2), v. Zool., 1890, p. 281. 
2 See account given by Tulk in Mag. Nat. Hist. xviii., 1846, p. 160. 
3 Entomological News (Philadelphia), vol. xi., Jan. 1900. 
