76 Trans. Acad. Sci. of St. Louis 
male in particular seemed to be biting the pair apart, and 
when I examined the spot after he had left I found that 
he had bitten away a large portion of the wing of his 
rival. I examined them at intervals for an hour, and 
found the pair still in copulo; the next morning they 
were separated, but there must have been some rivalry 
between the males, for two others had the wings badly 
bitten away. In another cage containing one female and 
four males, similar rivalry occurred; the female was pas- 
sive while the males ‘‘walked on stilts’? and protruded 
claspers. After some little display, three of these males 
retired and left her to the other suitor, which pursued 
her for fifteen minutes before he attempted to back under 
her. 
C. L. Turner” says the process of copulation in the 
cockroach is so rapid that the details cannot be followed; 
it can only be said that the male shoves his body under 
that of the female, and accomplishes the transfer of sper- 
matozoa in a few seconds. All those which I observed 
were much more deliberate, and in certain instances sev- 
eral hours were spent in actual mating. 
I have recorded* very similar courtship behavior for 
the wild roach, Parcoblatia pennsylvanica DeGeer, but 
here in the only case observed the female assumed the 
aggressive role. 
During the night males often go through mating ma- 
noeuvers with other males. 
Ezxudation.—In working with adults one soon notices 
at times a gathering of a thick, milky jelly on the ventral 
surface that seems to ooze out at the lines of demarca- 
tion of the last two segments. This is an almost trans- 
parent, slime-like substance of sufficient gumminess to 
22Ann. Ent. Soc. Amer., 9:122. 1916. 
18Trans. Acad. Sci. St. Louis., 24:57. 1922. 
