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plants of Asclepia Syriaca by the roadside, aud, if the season be a good one, he will hear 

 a concert that will probably be new to him. The performers usually found taking part 

 in such entertaintments in Canada are the Sphinges — cinerea, kalmice, gordius^ sordida, 

 hyaUy with " stars " of lesser magnitude. As the creatures recede from and approach 

 the auditor's stand-point, he will be able to mark very fine diminuendo and crescendo 

 effects. 



The wings of bees and other Hymenopterous insects are provided with catches, 

 which unite them on either side of the insect, so that, while beating the air in flight, the 

 two present but one resisting surface. Observing wings such as these, hooked together, 

 clean cut, stoutly nerved, and free from scales and feathers, and comparing them with 

 those of owlet moths, which are loose, ample, and heavy with scales, we can understand 

 how it is that their vibrations produce a clear, musical note, which strikes the ear, whilst 

 those of the latter fail to do so. 



The subject of colour, as regards insects, presents an interesting field, in vHich 

 comparatively few investigations have yet been made. Many unsolved problemr meet 

 the explorer at the very entrance. How is it, for instance, that the chlorophyll, in the 

 pulp and juices of leaves, having passed through the digestive organs of a caterpillar with 

 the nourishment that is assimilated to the substance of the creature, eventually develops 

 into the gorgeous hues and brilliant metallic embellishments which so frequently adorn 

 the imago ? What physiologist or chemist will make this clear to our perception 1 



Attention has been drawn to the fact that the insects that feed on the silk-weed 

 {Asclepia Syriaca) are generally coloured black and yellow or black and red. But who 

 can tell us why it is that the chrysalis which succeeds the caterpillar of Danais Archippus 

 is not of these hues, but of a delicate pale green ? 



That God has wonderfully ordered things, so that the colour of insects shall be a 

 safeguard to them, is apparent to the most casual observer. Some instances of this 

 providential care are more than usually interesting. The caterpillar of Sphhix quadri- 

 -Gornis feeds upon the elm. The leaves of the elm, when slightly injured, have a tendency 

 to curl up longitudinally, and the ribs of the leaf, which are prominent on the under side, 

 become, in the curled portions, very conspicuous. The larva of Sphinx quadricornis is 

 exactly the colour of the leaf, and has transverse markings that are the very counterparts 

 of its ribs. This resemblance is remarkable enough, but there is a further development 

 which is perfectly marvellous. As the season advances the curled portions of the elm 

 leaves become sere and dead, and S. quadricornis also changes its colour, and takes a 

 rusty brown hue. 



There is a genus of insects called Ennomos, the various species of which are known 

 in England as the "Thorns." We have in Canada a fine representative of the family in 

 Ennomos magnaria. The insects appear in their perfect state late in the autumn — our 

 own species (E. magnaria) appears in October. The interesting particular that I wish to 

 mention is, that in colour they all resemble " the yellow leaf " that is characteristic of 

 the season of their appearance. 



The English peacock butterfly {Vanessa lo), the American polyphemus moth, and 

 some others of the Lepidoptera, present in each instance, when displayed, the appearance 

 of a mask. When disturbed, the insects have, moreover, the trick of closing and expanding 

 their wings, which makes their touch-me-not grimness more striking. As the tiger has 

 been known to turn tail at the sudden opening of an umbrella, so the troublesome child, 

 or the busy titmouse would be likely to start back at the sudden presentation of the 

 -expanse of wing, with its eye-like spots and formidable markings. The flash of the 

 metallic spots on the " fritillaries " and the changeful sheen of the purple emperor 

 (Apatura Iris) may also act as deterents against attacks of predatory birds. 



The pleasing contrasts and exquisite harmony of colouring that are met with, not 

 only in the diurnal Lepidoptera, but in the night-flying species also, exemplify the truth 

 that " the works of the Lord are great, sought out of all them that have pleasure therein." 

 It is marvellous to find the most brilliant and attractive hues in insects that seldom, if 

 ever, meet the eye of the ordinary observer. Indeed, many an insect fails to reveal its 

 glories to the unassisted vision at any time. It is only through the microscope that the 

 richness of its velvet dress, or the hyaline splendour of its gauzy wings is made apparent. 



