BEHAVIOR OF THE COMMON ROACH. 359 



was sitting about a yard from a roach that was making her toilet. 

 Suddenly he exclaimed: "What powerful muscles those slender 

 antennae must contain." Those antennae do contain muscles 

 which are used in waving them in search of stimuli; but those 

 muscles are far too weak to bend the antennae into the mouth of 

 the roach. Had that visitor looked a little more keenly he 

 would have seen the roach bow its head, dart one of its forelegs 

 forward, catch in its bend the antenna of the other side and bend 

 it downward to the mouth. 



Sometimes, after a plunge into water, the antennae become so 

 wet that they are held together by capillary attraction and extend 

 forward and upward like the horn of a unicorn. In that position 

 they are out of the range of both of the forelegs. It is interesting 

 to watch the energetic and unavailing efforts of such a roach to 

 clean its antennae. Standing on its second and third legs with 

 the front part of the body elevated, it moves first one foreleg 

 and then the other after the antennae in such rapid succession 

 that it resembles a gymnast taking arm exercises. 



The palps of the maxillae and of the labium are cleaned by the 

 mouth-parts; but each palp is flexed into the mouth by its own 

 muscles. 



The body assumes a characteristic attitude while the legs and 

 the ventral side of the body are being cleaned by the mouth- 

 parts. Supported by the three legs of one side and by the hind 

 leg of the other, the roach, with the side supported by one leg 

 elevated at the expense of the other, reaches underneath her 

 body and gives her legs and it a good cleaning with her mouth- 

 parts. Again one is reminded of the behavior of a cat making her 

 toilet. 



To clean the dorsal surface of the abdomen, the roach uses 

 first one hind leg and then the other as a scraper or brush. With 

 these same legs the cercopods are thoroughly cleaned. In this 

 cleaning process the spines on the legs are quite serviceable. 



SENSATIONS. 



Plans have been formed to test rather thoroughly the senses 

 of the roach; but, since it will be a long time before the tests can 

 be completed, it is thought best to publish the following pre- 

 liminarv account. 



