102 BULLETIN 1369, U. S. DEPARTMENT OF AGRICULTURE 
type (fig. 38). These permit one to place the tips well into the hole — 
and then to open them and secure a firm hold on the grub. Another © 
type which has been found very successful is a simple forceps with — 
stout shanks and provided at the tip with minute mouse-teeth. 
These, however, often puncture the grub, which might be considered — 
objectionable by some. 
The enlargement of the grub holes in the hide by cutting, is a 
method suggested by some, especially by veterinarians. It has been | 
found that in most cases this practice causes the host too much dis- 
comfort. There is also the possibility of cutting through the cyst, 
if the incision is made too deeply, and thus allowing some of the 
foreign matter to enter the tissues of the host. - 
Certain stockmen have for years practiced the plan of puncturing 
the grub before attempting to extract it. This led the writers to 
Fic. 37.—Removing Hypoderma larve from back of cow by means of suction pump of 
the Brodersen type 
make a series of tests of this method. One of the procedures followed 
was to press firmly around the grub, thus bringing it up to the 
aperture in the skin, and then to clip the posterior end with a pair 
of fine-pointed scissors. A small amount of pressure applied to the 
cyst will expel the contents of the larva, after which the skin of the 
erub may be easily extracted by pressure. or better, with a pair of 
forceps. In certain instances grubs punctured in the way described 
were left in the host. In a short time it was found that the skins of 
most of these grubs had protruded some distance from the holes in 
the skin, thus enabling one to remove them easily with the fingers. 
EFFECT ON HOST OF DESTRUCTION AND EXTRACTION OF GRUBS 
Despite the very general practice of extracting grubs by hand 
which has been employed for many years, not until recently have 
