L. Harrison 
5 
also discarded Neumann's Menacanthus, which will have to come back 
into use. I put forward this list frankly as a basis for future re visional 
work, and not as anything in the nature of a final achievement. 
(iv) Scheme of Classification. This is briefly explained in the note 
which precedes it. It is simply a provisional scheme for the purpose 
of the present publication, and I do not wish to lay any emphasis 
upon it here. I thought at first of listing the species under genera 
following one another in alphabetical order; but eventually decided 
that it would be more desirable to have closely related genera, as 
far as possible, close to one another. 
(v) List of species and subspecies, valid and invalid, of Mallophaga. 
This constitutes the main part of the publication. The species are 
listed in alphabetical order under the 56 genera, the latter being in the 
order given in the Scheme of Classification. Specific and sub-specific, or 
varietal, names are not distinguished as far as validity is concerned. 
To each name is attached a record of the first technically valid 
description. My treatment of host distribution is due to considerations 
of space. Where there is only one host, that is given. But where the 
hosts become plural, or numerous, I indicate a genus, family, or order, 
as the case may be. Reference to Kellogg's List, or to the monographic 
works of Giebel and Piaget, will serve to give the actual known distribu- 
tion. As Professor Kellogg has announced the forthcoming production 
of a host list with modern nomenclature, I have not tried to anticipate 
this by interfering with the host nomenclature. On two points, however, 
I have exercised special care. For all species listed as invalid I have 
endeavoured to include the type host, for convenience should a question 
of reinstating the species arise ; and for species recorded from a suspect 
type host I have indicated, or suggested, the true host or host-group. 
Geographical distribution, since it is of little value, is only rarely 
indicated. 
No attempt has been made to apportion credit for the revisional 
work indicated by the synonymy. A great deal of synonymy has been 
copied from work to work, so that it would be a difficult, as well as an 
utterly useless, task to discover the first authority. I have reduced a 
number of species to synonyms myself, but they are not specially 
indicated. 
A number of species are included as valid, not because I believe 
them to be so, but because it is uncertain of what species they may be 
synonyms. Probably an equal number of species have been reduced 
to the rank of synonyms which future research will establish as perfectly 
valid. As I have said before, this publication is only to be considered 
