1985] Smith & Valentine — Grooming behavior in cockroaches 373 
at any point and clean it by slowly chewing from the point of con- 
tact to the end of the tarsus. 
2. Midleg Clean: As the ipsilateral foreleg is raised and the head 
turned backward, a midleg is raised and extended forward under the 
body and raised foreleg. The body is supported by the ipsilateral 
hindleg positioned slightly farther forward than usual, the three 
opposite legs, and sometimes by the side of the abdomen. 
3. Hindleg Clean: This movement resembles Midleg Clean. The 
foreleg is raised, followed closely by the midleg as the head dips 
down and back, and the hindleg swings forward underneath the 
raised fore- and midlegs. The tip of the abdomen is curled laterally 
toward the head, and the body is supported in a fourpoint stance by 
the curled abdomen and the three legs of the opposite side. If only 
the tibial apex or tarsus is cleaned, the midleg may remain in contact 
with the substrate. 
Certain features are common to all leg cleaning in all species. The 
leg is usually raised from the substrate, and is always held ventrally. 
Movement of the leg relative to the head is always posterior, back 
and forth movement in the mouth did not occur. Cleaning may 
begin at any level from coxa to tarsus, and once begun continues 
from point of contact to the end of the tarsal claws. The leg or parts 
of the leg may be cleaned once or several times in succession. There 
is no set order for legs to be cleaned, and leg cleaning may be 
interspersed with grooming of other body parts. 
Body Clean: Grooming the body with the mouthparts has only 
two modes in roaches. 
1. Sternum Clean: Sternal cleaning is well-distributed through- 
out the families and genera (see Table 2). The body is slightly raised 
by extension of the legs, and the forelegs are widely spaced. The 
head bends down under the body until the mouthparts reach the 
coxae of the forelegs. These and the area between them are cleaned. 
Similar cleaning of the sternal and coxal area of the meso- and 
metathorax did not occur. 
2. Pronotum or Wing Edge Clean: This is a much rarer move- 
ment than Sternum Clean , and was observed infrequently in only 
six species (see Table 2). The head is turned to the side and either the 
edge of the pronotum or the wing base just behind it is cleaned. 
rubbing. Involves progressive contact of body parts with other 
parts, or rarely, with the substrate. 
