18 
OctoBER 26th. 
MICROSCOPICAL MEETING.—MR. WONFOR ON 
“THE SCALES OF INSECTS.” 
By the term, ‘“‘the scales of insects,” was understood those 
epidermal appendages found on the head, thorax, legs, and abdomen 
of some insects; on the wing-cases of some beetles ; and on both 
surfaces of the wings of butterflies and moths: to whom they gave 
that wonderful beauty of colour which rendered them objects cf 
admiration even to the non-entomologist. 
In general terms (proceeded Mr. WonFor) scales might be designa- 
ted as being flattened hairs ; though in examining the multitudinous 
forms and varieties met with among insects, every stage between the 
round hair and the purely flattened scales was to be found. The 
analogy to hairs was also seen in their horny character, 
Taken as hairs, they seemed to present three different types : one 
very common form being an upper and lower surface, more or less 
rugous, striated, or wrinkled, with an inner structureless membrane 
between them, which seemed to act as a kind of foil to throw up the 
brilliant colours of the scales. In another type, the upper and under 
surfaces, without an inner membrane, were welded together ; for, 
when the scales were broken or damaged, no trace of the intermediate 
membrane could be found. In a third type, the scales were more or 
less rounded, sometimes tasselled, and devoid of the structureless 
inner membrane. In these last—and, possibly, also in the first type-- 
there seemed to be a power, on the part of the insect, of inflating, or 
puffing out the scales, so as, possibly, to render them more buoyant, 
Certainly, when taken from recently-caught specimens, these scales 
were rounded, but when pressed between glass they became flattened. 
Each scale was inserted in the wing-membrane by a stalk, and 
here, especially among the butterflies, the creatures not only appeared 
able to inflate, but also to raise the rows of scales. Some of the 
‘‘tasselled” scales, beside their points of insertion, had also a kind 
of ball-and-socket movement. When scales were taken from recently- 
caught specimens, a slight pressure of the covering glass caused an 
* oily substance to ooze from the point of insertion; but whether this 
was pigmentary matter, ora circulating fluid, was doubtful. 
