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spoken about scales and their markings within the last few years, 
are Royston Piggott, and those who incline to his ‘‘ beaded” theo- 
ries on the one hand, among whom must be included Mr. Slack, 
one of the Secretaries of the Royal Microsopical Society, and on 
the other, Col. Woodward, Dr. Maddox, Dr. Anthony, and Mr. 
McIntyre ; it is with the Jatter group I feel I must ally myself, 
because much if not all of the so-called structure described by Dr. 
Piggott, I believe is purely optical and not structure. Primarily, 
the scales of insects, and especially the Lepidoptera, are more or 
less flattened hairs of a cylindrical or tube-like shape, inserted by a 
pedicle, differing in character according to circumstances, into the 
wing membrane, on both sides of which they are arranged in sym- 
metrical rows like the tiles on the roof of a house. The majority of 
those on the wing, or rather the flat part of the wing, are flat or 
nearly so; interspersed among these are others quite hair-like in 
their character, and in some cases, to be alluded to presently, are 
some which are balloon-like in shape, and, we believe, are capable 
of being inflated like a balloon. We shall mention that from six to 
eight different kinds, or rather shapes, of scales, are found on each 
butterfly or moth, and when it is borne in mind how many thousand 
kinds of moths and butterflies are known to science, it may be 
imagined that though the varieties are not commensurate in num- 
bers with the varieties of the insects themselves, yet the varieties in 
shape and markings are very numerous. Anyone devoting a little 
time and attention to scales will be well rewarded for his pains, and 
will learn far more by comparison than he can possibly glean by 
studying one or two special scales. Among other points, he will 
find that the colour of insects is not always due to what to the eye 
appears as colour on the wings. A striking illustration of this is seen 
in the case of the common ‘‘Orange-tip,”’ the green colour on the 
back of the wings proves, on examination, to be produced by an 
intermingling of the black and yellow scales. Some certainly owe 
this colour to pigment, but in a great many it is due to the inci- 
dence of light, for if while under examination under the microscope 
the stage be rotated, as great a change will be seen in colour as 
with some objects under polarized light. Seen as transparent 
objects, brown seems the prevailing hue. Again, if scales are taken 
from living insects, or from those recently killed, and gently 
squeezed by pressure with a thin covering glass, greenish oily parti- 
cles will be seen to ooze from the pedicle, leading to the idea, that 
in the living insect there is something like the circulation of a fluid 
from the wing mentioned. It is certain they cannot require any 
fluid to repair waste or to accelerate growth, because they are of 
full size the instant the insect escapes from the chrysalis. There 
is no growth in the scales, any more than in the wings. The 
instant the moth or butterfly emerges from the pupa-case, it comes 
forth full grown, the wing membranes expand laterally and longitu- 
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