Ecological and Behavior Notes . 45 



Mutillids as to lead one at a casual glance to mistake the 

 beetles for wasps. 



Pterostichus luciihlandus Say. [E. A. Schwarz] was 

 abundant in the roads in the lowlands near the river dur- 

 ing the middle of August. Two of them were feeding upon 

 a dead moth, Estigmene acraea Dru. [H. G. Dyer]. 



Brachynus intermedius (?) [E. A. Schwarz]. A 

 specimen of this ** bombardier beetle" was observed in 

 Ma}', 1914, when it was a party to a little drama enacted 

 with a hop-toad. At about eight o'clock one evening the 

 toad was at the lights getting his dinner. I observed him 

 snap at an insect and just as quickly spit it out, where- 

 upon the prey rapidly ran away. I picked it up to 

 ascertain what this distasteful one might be. It ex- 

 ploded three times in rapid succession while in my 

 fingers. This caused a slight burning sensation of the 

 skin of the parts touched. 



Brachynus minutus Harr. [E. A. Schwarz] and 

 Braychynus cyanipennis. Several of these were taken 

 under stones by the roadside near Falling Springs, 111., 

 April 1, 1916. 



Selenophorus pedicidarius Dej. [H. S. Barber]. In 

 a vacant lot in St. Louis, July 14, 1915, this beetle had 

 its burrow. The hole was just wide enough that the 

 occupant's head blocked the entrance neatly. The resi- 

 dent beetle was kept busy keeping out a little beetle, 

 Saprinus posthumus Mars. [E. A. Schwarz] which was 

 making a very persistent effort to get into the hole. 

 Whenever the large beetle would retire to the bottom of 

 the hole, the little one would enter. The former had no 

 trouble in routing it out, since the hole was too narrow 

 for two, and the owner at the bottom of the hole had 

 the advantage of being able to push out the intruder. 

 During the half hour when I watched them, the little one 

 made about twenty attempts to enter. Then with the 

 forceps I pulled the larger beetle out and permitted the 

 little one to enter, then released the larger one and let 



