The Bulletin 
81 
Figure 53. Pupal cells formed of corn fiber for protection of pupa; emply pupal cell on left 
was formed in the soil just beneath corn stalk in which the larva completed its growth. 
Pupal cell shown in corn stalk was in natural position at lower end of feeding cavity. 
the amount of moisture seem to have much effect upon the duration 
of the pupal stage. Pupae kept in tight tin boxes with the air more 
than saturated with water emerged on the average in the same time 
as pupae which were exposed to the dry air of an average room or those 
exposed to the average humidity out of doors in a screened insectary. 
