110 PREPARATION AND MOUNTING 
The acarida, or mites and ticks, are well known; none, 
perhaps, better than those which are so often found upon 
cheese. Flour, sugar, figs, and other eatables are much 
infested by them; whilst the diseases called the iéch in man, 
and the mange in animals, are produced by creatures 
belonging to this tribe. These insects are sometimes mounted 
by simply steeping them in turpentine, and proceeding as 
with other insects. The Micrographic Dictionary gives 
the following directions as to mounting parts of these :— 
“The parts of the mouth and the legs, upon which the 
characters are usually founded, may be best made out by 
crushing the animals upon a slide with a thin glass cover, 
and washing away the exuding substance with water: some- 
times hot solution of potash is requisite, with the subsequent 
addition of acetic acid, and further washing. When after- 
wards dried and immersed in Canada balsam, the various 
parts become beautifully distinct, and may be permanently 
preserved.” 
Feathers of different kinds of birds are usually mounted 
in balsam when required to show much of the structure. 
This is particularly interesting when the feathers are small, 
as they then show the inner substance, or pith, as it may be 
termed, with the cells, &c. The “pinne,” or soft branches 
of the feathers, will be found of various constructions ; some 
possessing hooks along one side, whereby they fasten them- 
selves to their neighbours; others branching out, with 
straight points somewhat resembling the hairs from certain 
caterpillars. But, of course, when the metallic-looking 
gorgeous colours are all that is required to be shown, and 
reflected light used (as with the feathers of the humming- 
bird, peacock, &c.), it is much better that they should be 
mounted dry, as in Chapter III. 
The seeds and pollen of plants are most frequently 
mounted dry, as mentioned in Chapter III.; but the more 
transparent of the former, and the darker kinds of the latter, 
are perhaps better seen in Canada balsam. There is 
nothing particular to be observed in the manipulation, except 
