108 INSECTS AFFECTING DOMESTIC ANIMALS. 
It will be noted that all the cases so far cited show the larve to be 
mature in the latter part of summer or in fall, and in the specimen reared 
by Dr. Fitch pupation lasted through the winter and until the follow- 
ing July, which is quite different from the period of pupation in most 
of the bot-flies, ordinarily the pupa 
stage lasting but a few weeks and 
the winter being passed in the larval 
stage in the bodies of the host ani- 
mal. It 1s hardly to be supposed 
that eggs laid by an adult the last 
of July could mature by the middle 
of August, so we must infer more 
than one year as necessary to the life 
cycle of the insect, in some cases 
at least. 
July 31, 1885, Mr. George K. Cher- 
Fic. eee ore eg ee line rie, then a student in the Iowa A gri- 
Ree ee eae Pee cultural College, took two larve 
from the scrotum of a chipmunk, the testicles being entirely consumed. 
These he placed in alcohol, and the specimens now in hand correspond 
perfectly with the description of larva given by Dr. Fitch, except that 
Dr. Fitch states that the head end presents no appearance of jaws or 
other appendages, while in these spec- 
imens the hook-like appendages are 
distinct. Thesemight beso retracted, 
however, as to be inconspicuous and 
easily overlooked. 
The figures here presented (fig. 49) 
were drawn from specimens received 
through the kindness of Mr. George 
B. Starkweather. The details con- 
cerning their capture, etc., we repro- 
duce (see p. 107) from Insect Life 
- Fie. 51.—Cuterebra cuniculi: side view 
T 9 
(Vol. II, p. 216). (ena, 
If it is allowable to detail a life 
eycle from the records at hand it would seem that full-grown larve are 
found from the 1st of August until in October, and that within this 
time, probably, they escape from the host and burrow in the earth to 
pupate, remaining in the pupa stage until July of the following year, 
eggs then deposited requiring at least one full year for the growth of 
the larvee, and the life cycle being completed in not less than two full 
years. 
. THE RABBIT BOT-FLY. 
(Cuterebra cuniculi Clark.) 
Rabbits are infested with a very large bot, which attracted attention 
a century ago, the fly being named Gstrus cuniculi by Clark, and later, 
2 
