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flat, or nearly so ; interspersed among them were others quite hair-like 

 in their character, and in some cases, to be attended to presently, were 

 some which were balloon-like in shape and, he believed, were capable 

 of being inflated like a balloon. He should mention that from six to 

 eight different kinds, or rather shapes, of scales were found on each 

 butterfly or moth, and when it was borne in mind how many thousands 

 of moths and butterflies were known to science, it might be imagined 

 that, though the varieties were not commensurate in number with the 

 varieties of the insects themselves, yet the varieties in shape and 

 markings were very numerous. Anyone devoting a little time and 

 attention to scales would be well rewarded for his pains, and would 

 learn far more by comparison than he could possibly glean by study- 

 ing one or two special scales. 



Among other points he would find that the colour of insects was 

 not always due to what to the eye appeared the colour on the wings ; 

 a striking illustration of this was seen in the case of the common orange 

 tip, the green colour on the back of the wings proved on examination 

 to be produced by an intermingling of black and yellow scales. Some 

 certainly owed their colour to pigments, but in a great many it was due 

 to the incidence of light, for if, while under examination under the 

 microscope, the stage were rotated, as great a change would be seen 

 in colour as with some objects under polarised light. Seen as trans- 

 parent objects, brown seemed the prevailing hue. 



Again, if scales were taken from living insects or from those 

 recently killed, and gently squeezed by pressure on a thin covering 

 glass, greenish oily particles would be seen to ooze from the pedicle, 

 leading to the idea that in the living insect there was something like 

 the circulation of a fluid from the wing membrane. It was certain 

 they would not require any fluid to repair waste or to accelerate growth, 

 because they were of full size the instant the insect escaped from the 

 chrysalis. There was no growth proper in the scales, any more than 

 in the wings. The instant the moth or butterfly emerged from the pupa 

 case, it came forth full-grown, the membranes expanded laterally and 

 longitudinally, and by so doing the scales of the full size and in siiic 

 were simply drawn wider and farther apart, but of growth there was 

 none. This could be seen by cutting open the pupa case just before 

 the emergence, or taking the wing of a recently emerged insect This 

 must be done at once, because in some cases, within ten minutes of 



