The Butterfly Book. W. J. Holland
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INTRODUCTION
INTRODUCTION
CHAPTER I
THE LIFE-HISTORY AND ANATOMY OF BUTTERFLIES
"The study of butterflies—creatures selected as the types of airiness and frivolity—instead of being despised, will some day be valued as one of the most important branches of biological science."—Bates, Naturalist on the Amazons.
In studying any subject, it is always well, if possible, to commence at the beginning; and in studying the life of animals, or of a group of animals, we should endeavor to obtain a clear idea at the outset of the manner in which they are developed. It is a familiar saying that "all life is from an egg." This statement is scientifically true in wide fields which come under the eye of the naturalist, and butterflies are no exception to the rule.
THE EGGS OF BUTTERFLIES
The eggs of butterflies consist of a membranous shell containing a fluid mass composed of the germ of the future caterpillar and the liquid food which is necessary for its maintenance and development until it escapes from the shell. The forms of these eggs are various. Some are spherical, others hemispherical, conical, and cylindrical. Some are barrel-shaped; others have the shape of a cheese, and still others have the form of a turban. Many of them are angled, some depressed at the ends. Their surface is variously ornamented. Sometimes they are ribbed, the ribs running from the center outwardly and downwardly along the sides like the meridian lines upon a globe. Between these ribs there is frequently found a fine network of raised lines variously arranged. Sometimes the surface is covered with minute depressions, sometimes with a series of minute elevations variously disposed. As there is great variety in the form of the eggs, so also there is great variety in their color. Brown, blue, green, red, and yellow eggs occur. Greenish or greenish-white are common tints. The eggs are often ornamented with dots and lines of darker color. Species which are related to one another show their affinity even in the form of their eggs. At the upper end of the eggs of insects there are one or more curious structures, known as micropyles (little doors), through which the spermatozoa of the male find ingress and they are fertilized. These can only be seen under a good microscope.
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