GROWTH AND FEEDING OF HONEYBEE LARVAE. 
3 
On July 12, 20 eggs from the same colony, proving on microscopic 
examination to be only a few hours old, weighed 2.65 milligrams, 
average 0.132 milligram. On July 13, 20 eggs from the same frame 
weighed 2 milligrams, average 0.1 milligram. On July 27. 1916, 
20 eggs taken at random, and found on examination to be in differ- 
ent stages of development, weighed 2.3 milligrams, average 0.115 
milligram. Since newly hatched larva 3 weigh about 0.1 milligram, 
this may be taken as the average weight of eggs about to hatch, 
earlier stages being somewhat heavier. 
RATE OF GROWTH OF LARVAE. 
Data regarding the rate of growth were secured in 1915 and 1916 
for seven lots, five of these representing weighings made at 24-hour 
intervals (Table 1). The histories of these lots were as follows: 
Lot 1 (July 14, 1915). — Ten larva? of fairly uniform size from a 
single frame, surrounded by larval jelly which covered one-third to 
one-half of the bottom of their re- 
spective cells, were found to weigh 
exactly 1 milligram, and may 
therefore be considered newly 
hatched. About 50 cells contain- 
ing such larvae, all on the same 
side of the frame, were marked. 
Weighings were thereafter made 
at 24-hour intervals. 10 larvae taken 
at random being included in the 
first two weighings and 5 in each 
of the three succeeding. The 
weights of this and other lots are 
given in Table 1. On the third 
day there was evident a notice- 
able difference in the size of the 
larvae, one being appreciably larger 
than the others. This individual 
weighed 25.3 milligrams, the aver- 
age weight of the other four being 
only 12.75 milligrams. When seen curled up in their cells, larvae of 
this age occupy from 60 to 75 per cent of the diameter of the bottom of 
the cells. On the fourth day the weight of the smallest of the five 
larvae was 50 milligrams: that of the largest. 89.5 milligrams. The 
larvae at this time filled the bottom of the cells snugly and there was 
no trace of larval jelly. On the fifth day the two largest in the lot 
of five weighed together 328.15 milligrams, an average of 164.07 milli- 
grams. The remaining three together weighed 450 milligrams, an 
average of 150 milligrams. Two of the five were sealed, two not 
sealed, and one partly sealed. 
Lot 2 (June 28, 1916).— A number of cells on a single frame con- 
taining larvse chosen as newly hatched were marked. On June 29. 
10 larvae weighed 10.2 milligrams, or 1 milligram each, which is 
more than twice the weight of the larvae of the same assumed age 
in Lot 1. This of course means either that the larvae originally se- 
lected were too old or that the rate of growth during the first day 
was more rapid in this case. This difference continues up to the 
FlG. 1.- — Outline sketch of newly hatched 
honeybee larva, as seen through the 
microscope in conjunction with an eye- 
piece micrometer composed of a fine 
wire ring, having an inside diameter 
of 1.1 millimeters. 
