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hope you will not think that I mean the dog is so full of parasites 
that he is not a fit companion to man. Such an idea is foolish. 
AntHRopopa. InsEcTA. 
Pulea Serraticeps. Life History. Belongs to the order 
Insecta and the order Aphaniptera (no wings), which is properly 
a suborder of the Diptera or two-winged insects. They have two 
serrated mandibles used as prickers, two jaws or maxille and a 
single rigid tongue. Rudimentary wings in the form of plates, 
size 1-4 m.m.; remarkable power of jumping. Live on mammals 
and birds and pass from one host to another, female lays about 
twenty eggs in dusty corners of houses, or on any dust heap. 
Eggs hatch in about a week to a thirteen segmented larva with 
no legs, but having bristles. In ten days to a fortnight the larva 
spins a cocoon. From this emerges the young flea, which in 
another fortnight after changing in colour from white to brown 
becomes a perfect insect and at once proceeds in quest of a new 
host to torment. 
Nourishment by sucking blood. Distinctive marks. Species. 
Lice. Pediculi. Dog has two, cat one. 
Haematopinus piliferus, or true dog louse, 1-2 m.m. long, 
varies in colour from white to brown or purple. It buries head 
in the skin and sucks blood and causes a great deal of itching in 
most animals, but not so much so in dogs. Seen most on the 
shoulders, throat, lips and ears, especially in sporting dogs. 
Female lays a large number of eggs or nits, which are glued to 
the hair. Third generation from one female in two months may 
reach as many as 125,000 young lice ! 
Trichodectes latus, or broad-headed dog louse, does not suck 
blood but devours the scurf and skin and causes only very little 
irritation. They are very small and often escape observation. 
They are very interesting in connection with the tapeworms. 
Cxuass : ARACHNIDA. 
Order: Acarnia. These give rise to a disease of the host 
named Acariasis. Some of the families of this order are merely 
casual visitors, some eat the skin debris and hair and some are 
blood suckers. Many only cause slight trouble and the disease 
does not extend beyond the point of attack, whilst others, by 
rapidly increasing in numbers, by biting many times and by the 
poison they carry into the skin, their burrows in the skin and 
the intense irritation they set up cause a serious state of disease 
which is called scabies, or more commonly mange. One of the 
more simple (or non-psoric) Acariasis is that of the 
(a) Ixodidac or Ticks (wood mites). The common dog tick 
or Ixodesricinus. They have been recognised for many hundreds 
of years, and Aristotle speaks of them as Kunoraistes or dog 
