252 Transactions of the Academy of Science of St. Louis 
brunneus may pupate inside a single wheat straw and when it 
does, no nest is formed. Ouedius capucinus will pupate and 
orm a nest either in dirt or in old hay debris. Philonthus 
tetragenocephalus pupates above or below the surface of the 
ground, according to the moisture conditions of the habitat. 
LrencTH oF PupaL PeRtop. The length of the pupal period 
varies according to the species and also with temperature and 
moisture conditions. Either an excess or lack of moisture re- 
tards successful development. Low es retard while 
high temperatures accelerate developme 
When a pupa becomes too dry om ae has difficulty in 
freeing itself of the pupal exuvium and in consequence it will 
be delayed from several hours to several days. An excess of 
moisture may cause drowning or allow other factors such as 
mold to destroy the pupa. 
The temperature factor is not readily observed and is ap- 
parent only when one rears a large number of a single species 
under different temperature conditions. The breeding records 
for Philonthus cruentatus Gmel., show a distinct Sein in 
the length of the pupal period which is correlated with tem- 
perature conditions. Table J shows this variation and a the 
general temperature conditions prevailing during the pupal stage. 
Table JI charts the same data for Quedius capucinus and 
Philonthus tetragenocephalus. .The latter table is not as com- 
plete but it shows clearly that the variation in length of time, 
due to temperature, is not confined to a single species. 
In Table J, the larvae collected during the fall of 1925 were 
reared inside the building where they were influenced by arti- 
ficial heat as were those collected during the early spring of 
1926. The length of the pupal period of Philonthus cruentatus 
varied from seven to ten days, during late fall and early spring, 
at Bloomington. The larvae collected at Pendleton, Noblesville, 
near natural temperature conditions as possible at Winona 
Lake, Indiana. Winona Lake is in the northern part of the 
state and the temperature during June there is comparable to 
early spring at Bloomington. A few of the adults emerged in 
nine days while most of them required ten days. The collections 
made at Bass Lake, Tefft, Fowler, Pine Village, and Kern, 
Indiana, were carried to the extreme southern tip of the state 
where midsummer conditions prevailed. During this time the 
pupal period was cut from a maximum of ten days to a mini- 
mum of four days. About the middle of July larvae collected 
in southern Michigan were carried to northern Michigan. ese 
larvae showed a similar variation as did those collected in 
southern Indiana which were carried to the northen part of 
state. 
