PARASITOLOGY. 35 
herd by means of a sprinkling can or spray-gun will 
be found to be very effective treatment. The emul- 
sion is made as follows: 
R Kerosene.___-__-__--..-.__ gal. ii 
Common soap.______-____--- oviii 
Waterers jesse scone gali 
M. Sig.—Dissolve the soap in boiling water; add 
this solution boiling hot to the kerosene, stirring the 
mixture for ten minutes. 
When used this emulsion is usually diluted as fol- 
lows: One part emulsion to nine parts water: . 
HEMATOPINUS (Hema—blood, pinein, to drink). 
The species belonging to this genus are blood- 
suckers, and are much larger than the biting lice. 
They are bluish in color. The head, thorax and 
abdomen are distinct. The head is provided with a 
rostrum which projects anteriorly. It is arranged 
for piercing the skin and sucking blood. There are 
two simple eyes and two antennae (feelers). Each 
antennae is composed of four or five articles, or seg- 
ments. The thorax is wider than the head, and is 
provided with three pair of legs. The legs are 
short and strong, and the terminal segments are pro- 
vided with one or two hooklets. By means of these 
hooklets the louse is enabled to creep, and to hold 
on to its host. The abdomen is large and is usually 
composed of nine segments. The female is larger 
than the male. 
The following are the common species of blood- 
sucking lice: 
HEMATOPINUS ASINI (Asinus—ass). 
Synonym.—Hematopinus Macrocephalus. 
