270 
HERBERT OSBORN. 
have received specimens from Canada. If it is of rare occur¬ 
rence it may be considered as fortunate, for, if abundant, it 
would be rather difficult to contend with on account of the 
long wool of the host. 
The name indicates its characteristic feature, namely, the 
rounded head. The color agrees closely with the related 
species. 
Where it occurs it would be the best plan to pay close at 
tendon to destroying them at the time of clipping the sheep, 
even if they are but few in number, as at any other time the 
labor of making thorough applications for them is greatl) 
increased. 
The Biting Louse of the Dog. (Plate II, Fig. u). 
Trichodectes latus, Nitzsch. 
Something over a century ago DeGeer mentioned a specie 
•of parasite on the dog under the name oiRicmus canis , which 
probably referred to this species, and another mention by 0! 
fers under the name of Pediculus setosus probably preceded th 
description by Nitzsch under the name which the insect ha 
borne since 1818. 
Probably everyone who has had much to do with dogs i 
aware to what an extent this parasite may multiply and ho\ 
troublesome it is to this friend of man. It is generally be 
lieved that the lice are more troublesome to puppies than t 
old dogs, and it is not at all unlikely that the insects migrat 
when possible from older to younger animals. 
In color this species agrees pretty closely with the othe 
species and it is of about the same length as the cat louse, 
little more than one millimetre, but it is much broader i 
proportion, being more than half as wide as long, and th 
head is short and the front but slightly curved. 
The Louse of the Cat. (Plate II, Fig. io). 
Trichodectes subrostratus, Nitzsch. 
While it is possible that this parasite was referred to h 
Otto Fabricius about the year 1780 under the name of Pec 
