THE MANTIS.— THE NEST 87 



harden while a mass of spongy foam. If the nest is fixed 

 on a branch the base creeps round it, envelops the 

 neighbouring twigs, and assumes a variable shape 

 according to the accidents of support ; if it is fixed on 

 a flat surface the under side, which is always moulded 

 by the support, is itself flat. The nest then takes the 

 form of a demi-ellipsoid, or, in other words, half an egg 

 cut longitudinally ; more or less obtuse at one end, but 

 pointed at the other, and sometimes ending in a short 

 curved tail. 



In all cases the upper face is convex and regular. In 

 it we can distinguish three well-marked and longitudinal 

 zones. The middle zone, which is narrower than the 

 others, is composed of thin plates arranged in couples, 

 and overlapping like the tiles of a roof. The edges of 

 these plates are free, leaving two parallel series of fissures 

 by which the young can issue when the eggs are hatched. 

 In a nest recently abandoned this zone is covered with 

 fine cast-off skins which shiver at the least breath, and 

 soon disappear when exposed to the open air. I will call 

 this zone the zone of issue, as it is only along this bell 

 that the young can escape, being set free by those that 

 have preceded them. 



In all other directions the cradle of this numerous 

 family presents an unbroken wall. The two laterat 

 zones, which occupy the greater part of the demi-ellipsoid, 

 have a perfect continuity of surface. The little Mantes, 

 which are very feeble when first hatched, could not 

 possibly make their way through the tenacious substance 

 of the walls. On the interior of these walls are a number 

 of fine transverse furrows, signs of the various layers in 

 which the mass of eggs is disposed. 



