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Page:Popular Science Monthly Volume 90.djvu/107

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�The swallow-tail butterfly laying her creamy-white eggs on the anise

���The beautiful eggs of the swallow- tail butterfly as re- vealed by the film

��Popular Science Monthly

screen, two eggs are shown, bombarded by millions of spermatozoa. The fact that the fertilization of an animal egg is fundamentally the same process as that previously witnessed in the plant, drives home the essential similarity of the reproductive processes in the animal and vegetable kingdom. In every case fertilization consists in the fusion of two specially organized cells. After fertilization, the cell resulting from the union proceeds to divide into many cells, which finally colonize into what is then an embr\o.

From Egg to Golden-Winged Butterfly

Full of dramatic interest is that section of the film which depicts the life history of a butterfly — one of the "swallow-tail" variety famous for the yellow and black of its body and its "eye spots" of red and blue. A mother swallow-tail is shown on the screen laying her beautiful creamy-white eggs on the sweet anise. Four days later — on the screen only a minute later — a small black caterpillar emerges from one of the eggs. It feeds. In order to grow, it sheds its skin and emerges with a new and more beautiful one. Another period of feeding inter\-enes. Xow it is revealed spinning a silken lopp and attaching itself to a firm support. Then the mar\-elous process of skin-shedding is un- folded. A chr\-salis has been formed. For many months this hangs motionless. Then, as the film unreels, it suddenly shows signs of life. At the end of two days — a few seconds on the screen — it bursts open and releases a limp, curious insect with crumpled wings. This is the new butterfly.

So, other life processes are explained — those of the frog, the chicken, the rat. When the last foot of film has flickered past, you come away with the feeling that man himself is mysteriously linked with that simple protozoan which you saw in the beginning, and that the process of growth and development is the same in all the living universe.

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���A dramatic moment as the film unreels is that when the butterfly struggles out of the chrysalis. It has passed through many stages since the egg was laid, but now its limp wings expand and it soars away

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��Portion of the film showing the cater- pillar stage of the butterfly's life

���The butterfly flits joyously away after having emerged from the chrysalis

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