VO tess! 
45 
THE LOUSE OF THE SHEEP. 
(Trichodectes spherocephalus Nitzseh.) 
Redi is credited with the recognition of this species, and following 
him Linneus described it under the name of Pediculus ovis, and later 
still it was described in detail under the name given above. Denny’s 
reference to it would indicate it as rare in England and we have not 
met it here. If it is of rare occurrence 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- 
tention to destroying them at the time of clipping the sheep eae 
even if they are but few in number, as at any other time the F!6-33.—Tr- 
labor of making thorough applications for them is greatly Cte 
inereased. (After Denny.) 
THE BITING LICK OF HORSES, MULES, ASSES, ETC. 
( Trichodectes equi of Authors.) 
The original reference by Linnzus to the lice of horses and asses 
under the name of Pediculus equi most certainly refers to the common 
Trichodectes infesting these animals, but Piaget has reached the conelu- 
sion that this reference is to the form subsequently described by Giebel 
as Trichodectes pilosus, and that the form described by Denny as equi, and 
which has since almost universally been treated as the Linnzan species, 
was in reality a different insect from that described by Linnzeus under 
the same name. He therefore describes this form under the name o¢ 
parumpilosus. It is certainly somewhat confusing to be obliged to drop 
the familiar designation for so common a species, and were it not that 
this conclusion has been reached by one who is probably the highest 
living authority regarding these insects we should hesitate to introduce 
the change. The figures given by Piaget, however, leave no question 
that there is a decided difference between pilosus and parumpilosus, 
and it is equally certain that our common species belongs to the latter 
form; so, if there is no question as to Linneeus having the form pilosus in 
hand, we certainly have no right on technical grounds to apply the term 
equi to our common form. We will therefore introduce descriptions 
and comparisons of the two forms and adopt, for the present at least, 
and on the authority of Piaget, the names given in his ‘Les Pedicu- 
lines.” 
( Trichodectes pilosus Giebel.) 
This, according to Piaget, is the form originally designated by Lin- 
neus as equi, and which, if that is correct, was the basis for a name 
