The Biology of the Roach j 59 
by the fact that the species has continued unchanged 
and has flourished through so many centuries. 
While the cockroach is universally regarded as 
unqualifiedly loathsome, yet it offers its contribution to 
the welfare of mankind. FHaland’* tells us that it devours 
bed-bugs with great avidity, and that in Russia P. 
orientalis has long been used in powdered form and in 
other ways as a remedy for dropsy, and in other parts 
of the continent the powdered medicinal form of P. 
orientalis is sold under the name of Tarakane, as a 
remedy for pleurisy and pericarditis. 
Since roaches are universally regarded as vermin, it 
is natural that we should take it for granted that they are 
perpetually replenishing their population without regard 
to seasons. Careful observation soon leads to the dis- 
covery, however, that they, too, have their seasons, 
although perhaps not so sharply limited as are the life 
periods of those species that are obliged to conform to 
nature’s demands without the protection and provisions 
which human habitations supply, even grudgingly. 
Heretofore it has been thought that the roach requires 
several years to reach maturity. Sharp’ says, in speak- 
ing of the black beetle of the kitchen, referring to 
observations carried on by himself and Mr. H. H. Brind- 
ley, that the growth accomplished in several months 
being surprisingly little, ‘‘it is therefore not improbable 
that the life of an individual of this species may extend 
to five years.’’ In St. Louis, the life cycle of this roach 
from the hatching of the egg to the death of the adult 
is about one year. My notes show that in confinement 
all the adults die between July 1st and August 2nd, and 
‘Insects and Man, p. 281. 
be eit. p. 229. 
