Io SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 134 
be collected just inside the tops of cesspools and sewer manholes. In 
Queensland, Australia, P. australasiae is usually found in homes, 
while P. americana is more prevalent in sewers and manholes (Pope, 
1953). 
In southwestern Georgia, Blattella germanica outnumbered all other 
species of cockroaches inside homes, but Periplaneta americana was 
most prevalent (99 percent) in sewer manholes (Haines and Palmer, 
1955). Population pressure, it was concluded, may be a factor induc- 
ing movement from sewerage systems into homes. Haines and Palmer 
found that Periplaneta fuliginosa (Serville) was the most common 
cockroach in and around privies, but during the summer months the 
numbers of P. americana trapped in privies approached those of P. 
fuliginosa. What their data also show, but which these workers did 
not comment on, was that P. fuliginosa was, next to B. germanica, the 
most common cockroach inside homes. So far as we know, P. fuliginosa 
has not been examined for pathogens, yet its habit of frequenting both 
privies and homes suggests that such an investigation would be de- 
sirable. Periplaneta brunnea apparently was also trapped in significant 
numbers in both privies and homes during the warmer months of the 
year. 
Gould and Deay (1940) stated that Blatta orientalis frequently 
migrates into homes through sewerage and drain pipes, but they cited 
no specific observations. Fair (im Rosenau, 1940) stated that for sani- 
tary reasons the plumbing should be tight to prevent egress of cock- 
roaches and other vermin that may find their way into the drainage 
system. 
Eads et al. (1954) experimentally tested the ability of Periplaneta 
americana to pass through two common types of plumbing traps. 
American cockroaches were placed in a cage attached to one end of a 
P-type trap having the usual water baffle, similar to those used under 
sinks and wash basins (see photograph in Anonymous, 1953). An- 
other cage was placed over the other end of the trap. In the first test, 
1 of 16 cockroaches passed the barrier within 6 days. In a second 
test, 3 of 16 cockroaches passed the barrier within a few days. In 
another test, 49 cockroaches were caged at the lower end of a drum- 
type trap, of the kind used under bathtubs, that contained water as a 
deterrent. Within a week, 4 cockroaches had passed through the trap. 
This same information is given by Von Zuben (1955). 
Gary (1950) noted that in Houma, La., the sewage lift stations 
had always been heavily infested with cockroaches ; when the walls of 
the wet well were sprayed with insecticide, the men were almost driven 
out by the fleeing cockroaches. Gary instituted odor and cockroach 
