72 
J. HOPKINSON-CHEESE-MITES. 
The Tyroglyphidse, in their adult stage, are of very simple 
organization. Almost all are soft-bodied; they are without special 
breathing organs, without a heart, and without eyes, and their 
palpi, or organs of touch, are less highly developed than they are 
in many other families, while their mouth-organs also are com¬ 
paratively simple. They are very active, and do not appear to feel 
the loss of special organs of sense. 
They are not usually considered to be pretty creatures, and yet 
the commoner of the two cheese-mites, Tyroylyphus longior , seen 
under the microscope with a moderate power and with its smooth 
carapace reflecting a brilliant light, has some pretensions to beauty; 
and Mr. Michael says that “A female Glycyphagus Canestrinii, 
well seen with dark-ground illumination and a sufficient ampli¬ 
fication, its whole body surrounded by its peripheral row of great 
ostrich plume-like hairs, all shining like frosted silver, is a sight 
which will not readily be forgotten by anyone possessed of any 
appreciation of beauty.” 
I have taken the foregoing particulars from the first or intro¬ 
ductory part (183 pages) of Mr. Albert D. Michael’s “British 
Tyroglyphidse,” a work published by the Bay Society, which has 
just been completed by the issue of the second volume. The work 
is illustrated by 42 plates, most of which are coloured, each of the 
thirty species of mite described being illustrated by one or more 
figures drawn and coloured from life, while anatomical details, 
special organs, and dissected parts are uncoloured. The life-history 
of every species is traced through all its stages from the author’s 
personal observation and that of his wife, who, he says in his 
Preface, has shared in all his investigations with a “skilful hand 
in minute dissection and in microscopical preparation, and in the 
rearing of minute Acari.” 
