ARACHNOIDEA. OTF 
Feet gressorial, with coxe scarcely distant, unguiculate, not pro- 
vided with a vesicle or acetabulum. 
Oribata LATR. (Notaspis HERMANN). 
Sub-genera: Hopophora Kocu, Galumna V. Hryprn, Grrv. 
(Pelops Kocu, Oribates and Zetes ejusd.), Damaeus Kocn, (Lelba 
V. Heypen), Vothrus Kocu. 
Consult Otivier Eneycl. méthod., Ins. Vu. pp. §30—534. Most of the 
species live in mosses on the trunks of trees ; in some the body is girdled 
by a lamella produced on each side; Acarus marginatus DE GEER Mém. 
vu. Pl. vit. fig. 6, Notasp. humeralis Herm. Mém. Apt. Pl. 4, fig. 5 ;— 
—WNotasp. alatus Hur. Pl. 4, fig. 6, &e. 
Family V. JLvodea. Body defended by a coriaceous, extensile 
covering. Palps sheathing rostrum, with four joints; rostrum por- 
rect, truncated, composed of two lateral parts (mandibles ?), denti- 
culate at the apex, and a middle part (labium) covered with nume- 
rous recurved barbs. Feet with last jomt armed with a caruncle 
or vesicle, and with two claws. 
Ixodes LATR. 
Sp. Ixodes ricinus, Acarus ricinus L., DE GrER Mém, vit. Pl. 6, figs. 1—8, 
Lyonet Recherch. Pl. 6, figs. 1—8, Tick, Louwvette ; these animals live in 
woods, and attach themselves (the female) to different animals, especially 
to dogs ; from sucking the blood the body swells in form of a pea. The 
female is nearly 5’” long ; the male, much smaller, on copulating attaches 
itself beneath the abdomen of the female by means of the sucker, at the 
base of which the vasa deferentia open, to the vulva, situated at the fore- 
part of the body between the first and second pairs of feet. This singular 
copulation was already figured by DE Gump ; see also P. W. J. MUELLER 
in GERMAR u. ZINOCKEN Magaz. der Entomol. 11. 1817, s. 278—289. 
When laying her eggs, the female, according to the observations of FRIscH, 
gives out a clear fluid from her mouth, for fixing to her body the eggs, 
which the animal advances to her mouth ; hence the erroneous opinion of 
CHABRIER that the eggs are laid through the mouth. 
Ixodes americanus, Acarus nigua Di GEER Mém. vii. Pl. 37, figs. 11—13. 
Compare G. R. Treviranus, Zeitschr. f. Physiol. tv. 11. s. 185—191, Taf. 
XV. XVI. (probably Ixodes crenatus KoLLAR). This and other allied species 
known in America by the name of Piques are very distressing, and some- 
times dangerous to man and cattle. 
By the presence or absence of eyes (which are wanting in /xodes ricinus), 
and some other characters, Kocu has divided this numerous genus into 
several others. See Ericuson’s Archiv f. Naturgesch. 1844, 8. 217—239, 
and Uebersicht, 4tes Heft, 1847. 
Family VI. Gamasea. Palps free, filiform. Mandibles che- 
late, didactylous. Feet terminated by two claws and a caruncle or 
vesicle. QOcelli none, or indistinct. (Animalcules mostly parasitic). 
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