92 SOCIAL LIFE IN THE INSECT WORLD 



over the sides and at the base of the layer of eggs, and 

 projects through the meshes of the wire gauze as a 

 result of the pressure of the abdomen. Thus the spongy 

 envelope is progressively created as the ovaries are 

 gradually emptied. 



I imagine, although I cannot speak as the result of 

 direct observation, that for the central core, where the 

 eggs are surrounded by a material more homogeneous 

 than that of the outer shell, the Mantis must employ her 

 secretion as it emerges, without beating it into a foam. 

 The layer of eggs once deposited, the two valves would 

 produce the foam required to envelop the eggs. It is 

 extremely difficult, however, to guess what occurs 

 beneath the veil of foam-like secretion. 



In a recent nest the zone of issue is surrounded by a 

 layer of finely porous matter, of a pure matt, almost 

 chalky white, which contrasts distinctly with the 

 remainder of the nest, which is of a dirty white. It 

 resembles the icing composition made by confectioners 

 with whipped white of Qgg, sugar, and starch, for the 

 ornamentation of cakes. 



This snowy border is easily crumbled and easily de- 

 tached. When it disappears the zone of issue is clearly 

 defined, with its double series of leaves with free edges. 

 Exposure to the weather, wind, and rain result in its 

 disappearance, fragment by fragment, so that old nests 

 preserve no trace of it. 



At first sight one is tempted to regard this snowy 

 substance as of a different material to the rest of the 

 nest. But does the Mantis really employ two secretions ? 

 No. Anatomy, in the first place, assures us of the unity 

 ot the materials of the nest. The organ which secretes 



