192 ENTOMOLOGICAL NEWS [XXXI, '20 



located it. By this time she seemed to have decided that it 

 was futile to attempt to place it in the originally selected 

 location. She cleaned it (?) with her mouth parts, coated 

 its exposed side and ends with a secretion from her mouth 

 and from the bottom of the cage picked up loose bits of trash, 

 attempting to conceal the ootheca by covering it over with 

 them. Next she attempted to cover the ootheca with a 

 piece of paper. It did not suit her so she discarded it. 

 At about 3:45 A. M. she ran over to the opposite side of the 

 cage and ate bread. After about forty-five seconds she ran 

 up the pasteboard to the scar which she had made, chasing 

 other females away if they ventured too near. In the mean- 

 time one of the other females began to chew at the ootheca 

 as it lay unprotected upon the floor of the cage. Being 

 anxious to preserve it, I opened the cage, carefully lifted 

 the ootheca out, immersed it into water and placed it into the 

 scar, for the mother had left the scar when I opened the cage. 



At about 4:30 A. M. she returned to the ootheca in the 

 scar, discovered its presence there by feeling about with her 

 palpi, remained near it for several miutes, then left it and 

 stood more or less at one place upon the floor of the cage, 

 seemingly unconsciously gazing into space, occasionally 

 rubbing the cerci and the valves of her external genitalia 

 with the tibia of either hind leg. 



Often in the natural habitat I have observed the oothecae 

 of this species pasted to rafters or sills and covered with bits 

 of wood fibre which the mothers has chewed off with the 

 mandibles. Of those species among which it is customary to 

 deposit their oothecae, the oothecae are retained until places 

 of favorable moisture and thermal conditions are found. 

 Thus if a cage is too cold, too damp, too well lighted or too 

 poorly provided with material suitable upon which to ovi- 

 posit and for concealing of the ootheca, the mother bearing 

 it may retain it for several days. The following observations 

 upon retention of oothecae by Periplaneta americana Linn, 

 were made by the author of this article. 



In cages in which very favorable environmental conditions 

 prevailed ten oothecae were deposited each one day after 

 external appearance. 



