176 A NATURALIST IN BORNEO 



African species, and as the egg-case and latva of 

 Aspidomorpha miliaris, which I once found in some 

 numbers at Malacca, are very like those of the African 

 species, A. ptincticosta, the modus operandi of the egg- 

 laying females must be very similar. In some species 

 of Cassididce the eggs are deposited in an ootheca of 

 variable structure, which very roughly resembles that 

 of the Mantidce. In the genus Aspidomorpha the egg- 

 case, which is attached to a leaf or stalk of the food- 

 plant, contains a number of cells, formed by opposed 

 membranes, each containing an egg. The way in 

 which the ootheca of the African species is formed 

 is as follows : The beetle, having selected a suitable 

 spot, plants her front feet firmly and does not move 

 them throughout the operation ; the hind pair of legs 

 are held up out of the way. "The abdomen is then 

 extended and the oothecal plates extruded. Placing 

 the tips of the plates against the surface of the leaf, 

 she exudes a small quantity of colleterial fluid which 

 adheres to the leaf. [This fluid is secreted by certain 

 glands, accessory to reproduction, situated at the hind- 

 end of the body. R. S.] Then compressing the 

 oothecal plates together and moving the abdomen 

 upwards this fluid is drawn out between the plates 

 as a thin membrane. Having attained the limit of 

 the upward movement, the two oothecal plates are 

 moved laterally upon one another, so that the mem- 

 brane is cut off. It rapidly dries and becomes hard 

 on exposure to the air, and is then tough and elastic. 

 To form a second membrane she brings the tip of the 

 abdomen again to the surface of the leaf, but a little 

 on one side of the point of attachment of the first 

 membrane, again exudes some colleterial fluid, and, 



