40 VETERINARY PARASITOLOGY 
the back in cattle; and various so-called insect powders, 
such as pyrethrum, stavesacre seeds, etc. 
Decoction of tobacco (1 in 20) is often used. 
Sheep may be dipped. 
The same precautions as regards disinfection should 
be taken as in mange. 
A mite which sometimes causes symptoms allied to 
those of Phthiriasis is the Dermanyssus gallina, or fowl 
mite. This often attacks horses kept in a stable in 
which fowls are in the habit of roosting. Dermanyssus 
avium may cause similar symptoms, and their presence 
is said to result from swallows or sparrows nesting in 
the roof of the stable. The mites attack chiefly the 
neck, withers, and back, causing loss of hair and a 
scurfy appearance of the skin, accompanied by intense 
pruritus and constant rubbing. 
The mites can usually be found:on the skin. 
Treatment is similar to that for phthiriasis. 
Pulicide (Fleas). 
On dogs Pulex serraticeps is common. It is large, and 
brown in colour, while Pulex iyritans of man is smaller 
and darker. 
The complex life-cycle may take place on one host. 
This is often observed in the cat, especially in long- 
haired varieties, on the skin of which often a consider- 
able number of comparatively large white eggs may be 
found. 
Symptoms.—There is constant irritation and scratch- 
ing, and occasionally an eruption may be seen on the 
back. Fox-terriers seem particularly liable to this 
eruption, and in these it takes the form of dark-coloured 
circumscribed hairy patches, with irregular surfaces. 
They are frequently confounded with mange, ringworm, 
and other skin affections. 
Treatment.—Creolin baths are most useful. In the 
