256 Wisconsin Academy of Sciences, Arts, and Letters. 
might be crowded into crevices, in the comb or in boards, and 
flattened on one, two, or three sides. The eggs of one female 
might show all these variations. 
Effect of Temperature 
In trying the effect of temperature on the length of the life 
history of G. mellonella L., four different temperatures were 
used: namely, room temperature (24°C.), 29°C., 37°C., and 45°C. 
Boom temperature. Eggs laid from September 23 to September 
28, 1918, hatched about October 23, and the larvae were placed 
in glass finger bowls and small homeopathic vials containing brood 
wax. The dishes were left in the laboratory, where the tempera¬ 
ture was about 24°C. The larvae grew very slowly and were 
rather inactive during the winter months. On February 13, 1917, 
they averaged 6.5 mm. in length; on June 4, 1917, the average 
length was 10 mm., or about one-third the mature length. As a 
result of their slow growth, only part of a generation, the egg 
stage, could be used in comparing their life history with that of 
the larvae kept at higher temperatures. In the experiment not 
less than 20 larvae were used. From September 23, 1916, to June 
4, 1917, only part of a life cycle was completed, the egg stage and 
part of the larval life. 
29°C. A temperature of 29°C. was maintained in a constant- 
temperature compartment by using a 16 candle power carbon elec¬ 
tric light globe. 2 On March 10, 1917, half-grown larvae were placed 
in several large crystallizing dishes in which was a brood comb for 
food; these dishes were placed in the constant temperature compart¬ 
ment. A large evaporating dish filled with water was placed in 
the compartment to keep the atmosphere moist. The larvae grew 
rapidly and were very active. Soon after pupation occurred, 
moths of average size hatched, first males and then females. Mat¬ 
ing took place, and from the eggs laid, larvae hatched. The aver¬ 
age life of the moths was five days for females, seven days for 
males. From this point on, the moths went through their life 
cycle rapidly; from March 10 to May 29, 1917, when the last ob¬ 
servation was made, there had been three generations. The num¬ 
ber of larvae and moths in each generation was very large, being 
not less than five hundred. 
2 The temperatures of 29°, 37°, and 45° C. were obtained in the three com¬ 
partments respectively by experimenting with electric light globes of different 
powers until those continuously giving the desired temperature were procured. 
