Or 
a) 
STUDIES ON PERILLUS BIOCULATUS FAB. 
The following topics are discussed : 
Classification and synonomy of Perillus biocu'atus 
History and distribution 
Methods of rearing 
Life history 
Life cycle 
Egg cluster 
Oviposition 
Fecundity of females 
Incubation 
Hatching 
Nymphal instars 
Feeding habits of nymphs 
Habits of edults 
Mating habits 
Length of life 
Hibernation : 
Determining the fatal minimum temperature by the thermoelectric method 
Economic importance of Perillus 
Kinds of insects fed upon by Perillus 
Technical descriptions 
The egg 
Nymphal instars 
The adult 
Color varieties 
_ Nature of the color pattern 
Chenge of color in adult 
Relation of temperature to color forms 
Relation of color to sex 
Conclusion 
Perillus circumcinctus Stal 
Notes on the life history of Perillus circumcinctus 
Literature cited 
Classification and Synonomy 
The double-eyed soldier-bug was first described by Fabricius (1775) 
as Cimex bioculatus, from specimens which had been collected in 
America by Drury. The same author in his later works (1781, 1787, 
1794, and 1803) records the species by repeating the original descrip- 
tion but without adding additional information. Goeze (1778) and 
Gmelin (1788), both record Cimex bioculatus, but merely transcribe 
the original description by Fabricius. 
Thomas Say (1825) described this species as new, under the name 
Pentatoma clanda, and recorded it as inhabiting “Missouri.” Say states 
that the species is very variable and describes varieties a, b, and c. Stal 
(1872) placed bioculatus in his genus Perillus, which in 1862 he had 
