416 



NATURE SKETCHES IN TEMPERATE AMERICA 



vation of the ground which eflFectually destroyed their eggs 

 has gradually controlled these enormous swarms of locusts, 

 so we rarely witness the clouds of these insects seen some years 



ago. 



The Pennsylvania Cockroach 



Few of us realize the great al^imdance of insect life that can 

 be found in old stumps. I recall my surprise at pulling off 

 some bark of an old tree stump one day to discover a horde of 

 cockroaches secreted there. But so quick were they in their 

 movements to escape that I could hardly get a satisfactory 

 glimpse of one of them. At this time the question arose as to 

 whether these insects were simply our common household 

 pest, lilatta oricntalis, or a wild species. More recently. 



The Pennsylvania Cockroach (Ischnoptera pennsylvanica), 



one of the most common of our roaches, living under 



loose bark. Male, female, and cast skin. 



June 1, 1005, an opportunity came again to look into this 

 question and I satisfied myself that what I formerly saw on 

 the old tree stumps was the wild species, the Pennsylvania 

 cockroach, which in scientific terms is known as Ischnoptera 

 pennsylvanica. I have dei)icted the male, female, and a nymph 

 cuticle in the accompanying photographic illustration. On 

 the day mentioned I was in an open wooil at Flossmoor, Illi- 

 nois, when I noticed a number of oak stumps. Here under 

 the loose bark that peeled off cpiite easily, I encountered a large 

 number of these cockroaches. 



