1985] Smith & Valentine — Grooming behavior in cockroaches 375 
Antenna- Foreleg Rub: This movement was performed by all spe- 
cies observed except C. punctulatus. The basal segments of the 
antenna not reached by the mouthparts during Antenna Clean are 
groomed by rubbing. The base of the antenna is caught in the crook 
of the tibio-femoral joint, and the foreleg very deliberately and 
slowly moves down in a scraping motion. This movement is often 
followed by Foreleg Clean, but is not consistently combined with 
Antenna Clean. 
Head-Foreleg Rub: Two forms were observed (see Table 3). 
1. Eye- Rub: This movement was observed in all species but C. 
punctulatus. The foreleg is raised and the area of the tibio-femoral 
joint contacts the eye just below the antennal base. The leg moves 
straight down in a short, sharp rub reaching most of the eye surface. 
2. Low Face Rub: This movement was observed in all species. It 
is similar to Eye Rub, yet distinct. The area of the head contacted is 
restricted to the lateral mouth region. 
Prothorax-Foreleg Rub: Individuals of a single species, Supella 
longipalpa, raise a foreleg so that the femur contacts the lateral 
margin of the prothorax and performs a quick series of two to five 
posterior strokes. 
Abdomen- Hindleg Rub: This movement is well-distributed 
throughout the families. Only two blaberid species, Archimandrita 
tessellata and Gromphadorhina portentosa, were not observed to 
perform some type of abdomen rub. Dr. Louis M. Roth, in a most 
useful review of this manuscript, informs us that some other blaber- 
ids omit abdomen or wing rubs. He points out that the bodies of 
Laxta females are often solidly caked with dirt, and the tegmina of 
Therea nuptialis have small setae which retain debris and make the 
insects less conspicuous. 
A hindleg is used to rub the dorsal, ventral, and/or lateral sur- 
faces of the abdomen. The movement is always unilateral: an insect 
may alternate sides rapidly, but only one hindleg ever touches the 
body at one time. The direction of the rub is posteriad. Often, but 
not consistently, abdomen rubbing is followed by hindleg cleaning. 
Cercus- Hindleg Rub: Cercus rubbing is present in most of the 
species observed (Table 2). Cercus- Hindleg Rub is a separate and 
elaborate movement quite distinct from abdomen rubbing. The 
ipsilateral hindleg rubs any part of the cercus; at times, only the very 
tip. The abdomen may or may not be curled toward the rubbing leg. 
