66 BULLETIN 1369, U. S. DEPARTMENT OF AGRICULTURE 
Only four adults of H. lineatum were bred out in Middletown, 
N. Y. Among these the pupal period ranged from 26 to 41 days, and 
the period from date of leaving the host to emergence of the adult 
ranged from 27 to 42 days. At Dallas, Tex., this period of trans- 
formation ranged between 18 and 77 days, with an average of 41.7 
days in the case of 221 specimens kept out of doors. 
The average period of transformation was slightly shorter in males 
than in females, being 42 days in the former and 44.4 in the latter, as 
computed on 92 males and 80 females. 
Hadwen (33) has presented records of the duration of the pupal 
stage of 7. lineatum of from 13 to 19 days when the specimens 
were kept in an incubator at 32° C., and Glaser (30) records a pupal 
period in Germany for this species of 23 to 38 days. Carpenter 
(72, 17) states that 
he has observed the 
pupal _period to be 
about 7 to 8 weeks in 
Ireland. 
PREPUPAL AND PUPAL 
STAGES OF HYPO- 
DERMA BOVIS 
Mature larve of 
1. bovis show about 
the same degree of 
activity after emer- 
gence from the host 
as those of H. line- 
atum, but they seem 
to have a stronger 
tendency to burrow 
Fic, 31.—Heifer with bagging around body for urpose of puta tie so a 
| eee cattle grubs as they emerge for: Host larvee of this Species 
also show a great de- 
sire to escape from direct sunlight, and one was observed to crawl 
12 feet to a deep shadow, where ‘it pupated. If placed on loose soil, 
most of them will bury themselves in a short time. Some burrow 
down about an inch, but most of them go just below the surface. - 
When the weather is warm the prepupal period is very short.- At 
Dallas records were kept on several larvee which emerged normally 
from cattle. All of these pupated, and 4 produced adults. The 
prepupal period of these larvee was in every case somewhat less than 
a day, and the pupal period of the 4 which emerged was from 14 
to 15 days, making a total period from emergence from the host to 
the appearance of the adult insects of from 15 to 16 days. Among 
24 larve extracted from cattle at Dallas, Tex., and kept for rearing, 
14, or 58.3 per cent, pupated and only 1 (4.2 per cent) produced 
an adult. In the case of this specimen the prepupal period was 
slightly more than a day, and the pupal period 14 days, a total 
transformation period of 15 days. The writers succeeded in breed- 
ing out 4 adults from 8 mature larve extracted from cattle at 
Herkimer, N. Y. (Table 9). The prepupal period among these was 
10 hours to 1 day, and the pupal period from 15 to 24 ‘days. The 
total developmental period from extraction of the larvee to the 
