132 
modern system. 
Acarus geniculatus. Linn. . p 
Inhabits trees and beneath stones. It >s common in Sweden, Ger 
many, and England. 
Genus 5. NOTASPIS, Hermann. _ 
Body covered by a coriaceous skin, the anterior part rostrated, the pro- 
duced part inclosing the organs of mastication : abdomen subglobose, 
the sides anteriorly with a wing-like process : tarsi with claws. 
Sp. 1. Not. humeralis. Abdomen blackish-chesnut; the produced pa 
membranaceous. T , 
Mitte a rebord. Tie Geer. Oribita humeralis. Latr., Lead, 
Inhabits moss and beneath stones. It is not uncommon m the south 
parts of Devonshire. 
Conus 6. ACARUS of authors. 
Body soft : mouth naked : torsi with a pedunculated vesicle at their . 
tremities. , . , »u p 
Sp. 1. Actt. domeUicus. White, with two brown spots ; body ovate, ttit 
middle coarctate, with very long hairs : legs equal. 
Acarus Siro. Linn., Fair., Leach Edm. Encyd. vn. 415. Acarus do 
mesticus. Latr., Leach Sapp, to Encyd. Brit. 1. 444. 
Inhabits houses, living in cheese and flour that have been kept too. 
long. 
B. Mouth furnished with a rostrum. 
Fam. IV. Ixodiawe. Leach. 
Eyes obscure or concealed. 
Stirps. 1 . — Palpi and rostrum exserted. 
Genus 7. IXODES. Latreille, Leach. Cynorhcestes. Hermann- 
Palpi equally broad, longer than broad. 
Sp 1 Xr. Bicinus. ScuUim rounded, smaller; with the vagina ot th e 
rostrum and the legs fuscous : abdomen varying in colour. 
Acarus lticinus. Linn., Eahr. Ixodes Ricinus. Latr., leach. 
Inhabits Europe, attaching itself to dogs. In Britain it is called the 
^Dr. Leach has written a paper on the British species of this g L ^ 
nus, which is published in the eleventh volume of the Transaction 5 
of the Linnean Society. 
Stirps 2 . — Palpi and rostrum hidden. 
Genus 3. UROPODA. Latreille, LeaeL * _ 
Body oval, orbiculate : back corneous, clypeil'orm, the disc being g 
dually convex; beneath flat: anus produced into a long filiform 1 
duncie (by which it adheres to coleopterous insects) : legs very snu 
pressed close to the body, the first pair shortest, the second l‘ 
rather longer, the third distinctly longer, the fourth pair longed- 
