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Psyche 
[Vol. 92 
Discussion 
Prior to discussion of specific grooming movements, several gen- 
eralized comments can be made regarding all species observed. 
Except for Abdomen-Substrate Rub observed in two species, 
grooming in roaches is restricted to cleaning, or rubbing one body 
part with another. Other orthopteroids are known to utilize droplets 
of fluid in grooming (Allard, 1929). Though some individuals 
observed in this study placed droplets of clear fluid from the mouth 
onto the substrate, none utilized the droplet in grooming. 
Though isolated grooming movements are often interspersed with 
periods of general activity, the most extensive and complete bouts 
are nearly always preceded by periods of relative quiet lasting two to 
seven minutes. No set sequence of grooming movements is discern- 
ible in any individual or species. Any combination or sequence of 
movements is possible, including repetitions of a particular move- 
ment. Larger species 45 mm) display a strong tendency to per- 
form all grooming movements less frequently than the smaller 
species. 
Generally, the use of flour as a stimulus has its greatest effect in 
simply increasing the frequency of movements in the next grooming 
bout. However, some species perform movements in the presence of 
flour which are not observed in its absence. Such movements are 
noted in Table 2 by an asterisk. Movements that are most consist- 
ently affected are basal antennal rubbing, abdomen rubbing, wing- 
abdomen rubbing, and wing flipping. 
An overall inhibiting factor is the presence of barometric low 
pressure. In advance of fronts and when under low pressure cells, all 
species exhibit a tendency to remain relatively quiet. 
With a single exception, all species quickly became habituated to 
sunlight and artificial light. Grooming activity is readily performed 
at any hour of the day or night, even in bright light. Blaberus 
craniifer presents the single exception. In this species, the only 
grooming performed in daylight or lamplight was antenna and palp 
cleaning. Whether or not dusted with flour, when exposed to light 
the animal cleaned only the antennae and palpi, then arranged itself 
with the head, antennae, and legs drawn under the pronotum and 
wings, and sat unmoving until darkness fell or it was placed in a 
dark environment. During dark hours, the animal could be heard 
moving vigorously around the cup. On numerous occasions, the 
