644 LAURA FLORENCE 
Pediculidae. He points out that the order Anoplura Leach 1817 contains 
two suborders — Siphunculata Meinert 1891 and Mallophaga Nitzsch 
1818 — and says (page 332 of reference cited): ‘‘Since, however, the name 
Anoplura Leach (1817) was applied to both Siphunculata and Mallophaga, 
and in this sense agrees with modern views, it should henceforth be used 
in its original sense only, there being no justification for continuing to 
apply it to Siphunculata alone.” 
BIOLOGY 
The hog louse is the largest louse affecting domestic animals and is of 
common occurrence wherever the hog is found. The hog is its only host, 
and when not molested the parasite is likely to increase in large numbers 
and cause an unthrifty condition in a herd. The lice frequent the folds 
of the skin on the neck and the jowl, the inside and the base of the ears, 
the inside of the legs, the flanks, and, in smaller numbers, the back, where 
they crawl under the scales to get in contact with the new skin. They 
are well adapted for experimental work, because they are easy of access 
and feed readily on man, while their size and their habit of taking hold 
of any object placed in front of them lessen the difficulty of keeping them 
in confinement. 
From the time of hatching, hog lice feed readily on man if they have 
not become weakened through too long fasting. During the course of 
this investigation hundreds of lice have been fed on the forearm without 
any resulting reaction, except, in a few cases, a slight redness which 
disappeared within half an hour, and, in cases in which the mouth parts 
were inserted but no blood was drawn, a slight swelling which disappeared 
within an heur. This is contrary to the finding of Sikora (1915:536), 
who saw no reaction on the first or the second day of the feeding but states 
that thereafter the skin turned red in an area from 1 to 5 millimetersaround 
the point of puncture and swelled slightly, remaining thus for more than 
twenty-four hours. Recently Moore and Hirschfelder (1919:8) have 
published a detailed account of serious pathological effects of the bite of 
the clothes louse and clinical observations of the resulting illness. Accord 
ing to Stevenson (1905:12), 
Stockmen handling hogs often become temporary hosts of the louse, but it has neve 
been known to remain for any length of time on the human body and is not known to exis 
on any animal other than the hog. Attempts made at this laboratory [United States Burea 
of Animal Industry] to propagate Haematopinus suis on dogs have met with repeated failure 
