256 THE POPULAR SCIENCE MONTHLY. 



INSECTS' EGGS. 



BT M. V. BRANDICOURT. 



"TOHANNES SWAMMERDAM, a Dutch naturalist, who was 

 *J the first to examine insects with a microscope, and whose 

 investigations were published in 1757, gave some curious details 

 concerning the eggs of insects.* " Some are oblong," he said, 

 "others ovoid or round. There are also angular, pyramidal, 

 striated, and granular eggs, etc. They are no less various as to 

 colors, and we find them white, yellow, red, blue, green, and pied 

 with different colors so singularly combined that it is almost im- 

 possible to describe them exactly. In consistence, some are soft, 

 others hard ; some membranous, others covered with a coat like 

 parchment or with a real eggshell ; some are covered with a kind 

 of froth, others with hairs." 



Swammerdam described with many details the eggs of the 

 Nepa cendrea, a little fresh-water hemipter, which he called the 

 water scorpion (Fig. 10). They are yellow and nearly of the same 

 shape as the seed of the blessed thistle, slightly elongated, and 

 rounded at the lower end. On the upper part they are provided 

 with seven or eight slender branches, or hard threads, of which 

 the point is red and the middle whitish. These appendages or 

 threads, arranged in a circle around the circumference of the sum- 

 mit of each egg, form a kind of open egg cup, which receives the 

 end of the next egg in its cavity. Thus these appendages of the 

 first egg hold the lower end of the second, and so on. 



The eggs of the Lepidoptera have considerable resemblance 

 to the seeds of plants (Figs. 1, 2, 3, 4). "Those of the larger 

 and smaller cabbage butterflies have the shape of a pyramid, of a 

 height three or four times the diameter of the base, and the base 

 is stuck to a leaf. The eggs are usually formed by eight rounded 

 ribs, separated by flutings running from the summit to the larger 

 end. On each of these sides may be seen an infinite number of 

 flutings parallel to the base. The eggs of the great tortoise but- 

 terfly are nearly spherical, and are smaller ia diameter at the base, 

 or the part by which they are attached to the plant, than at the 

 summit, whence eight equally distant crests descend along the 

 body of the egg, forming ribs which diminish imperceptibly in 

 height and disappear before reaching the end." \ 



These eggs resemble those of a night moth which attaches its 



* Histoire naturette des Inscctes (Natural History of Insects). Translated from the Biblia 

 Natures of Johannes Swammerdam. Paris, 1758. 



\ Histoire naturette des Insectes (Natural History of Insects). By De Tigny. Paris, 

 1815. 



