372 CHAPTER ON MITES. 
skin of the hand, in this case, however, of cleanly persons. 
Mr. Cameron states that “the kind of sugar which is both 
healthful and economical, is the dry, large-grained, and 
light-colored variety.” 
Closely allied to the preceding, is the Cheese-mite (Aca- 
rus siro Linn.), which often abounds in newly made cheese. 
Lyonet states that during summer this mite is viviparous. 
Acarus farine DeGeer, as its name indicates, is found in 
flour. Other species have been known to occur in ulcers. 
The itch insect (Sarcoptes scabiei DeGeer, Pl. 6, fig. 7) 
was first recognized by an Arabian author of the twelfth 
century, as the cause of the disease which results from its 
attacks. The body of the insect is rounded, with the two 
hind pair of feet rudimentary and bearing long hairs. It 
buries itself in the skin on the more protected parts of the 
body, and by its punctures maintains a constant irritation. 
Fig. 6. Other species are known to infest the sheep and dog. 
TA, Another singular mite is the Demodex folliculorum 
» (Fig. 64), which was discovered by Dr. Simon, of 
Berlin, buried in the diseased follicles of the wings 
of the nose in man. It is a long slender worm-like 
form, with eight short legs, and in the larva state has 
degraded of the order of Arachnids. We figure on 
plate 6, figs. 8 and 9, greatly enlarged, a most sin- 
pains mite, disebrered by Newport on the body of a larva 
of a wild bee, and described by him under the name of Hete- 
ropus ventricosus. Fig. 8, in the plate, represents the body 
of the fully formed female. After attaining this form, its 
small abdomen begins to enlarge until it assumes a globular 
form (Fig. 9), T thie maia of. mites-look like’ little: beads: 
Mr. Newport was unable to discover the male, and thought 
that this mite was parthenogenous. It will be seen that the 
adult Demodex retains the elongated, worm-like appearance 
of the larva of the higher mites, such as Typhlodromus: 
This is an indication of its low rank, and hints of a relation- 



six legs. This singular form is the lowest and most : 
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