150 Proceedings of the Royal Physical Society. 
the genitalia, but it is an advantage to keep females in as lifelike a condition 
as possible. The only examples liable to be affected by the strong spirit are 
those which have newly moulted. Specimens intended for mounting in 
balsam may be put in a mixture of 3 parts of absolute alcohol to 1 part 
of glacial acetic acid. So treated they die with legs and other appendages 
extended, and a good deal of the internal fat is removed at the same time, so 
that a less prolonged treatment with caustic is required before mounting. 
In collecting Mallophaga a diary should be kept of hosts examined, with 
under each entry a rough note of the genera and species found. After a time 
the insects may be separated and each lot labelled and card-indexed. 
Before examining a bird it is well to plug up shot wounds (where 
Mallophaga, especially Liotheids, migrate and frequently get clogged up in 
blood), the nostrils, throat, and even the anus. Such precautions are very 
necessary in the case of the Auks. The oleaginous contents of their stomachs 
exuding, quickly soil the plumage in the region where the search for parasites 
is most likely to be rewarded. Owing to their short stiff feathers Auks may 
be thoroughly examined without recourse to the hand plucking so often 
necessary. If one’s search is prolonged, the great bulk of the parasites 
present may be gathered from round the eyes and below the bill where, given 
time, they obligingly congregate. 
During examination the birds should be isolated on white sheets, or kept 
in cotton bags. All hosts indeed should be separately packed from the first, 
and never allowed to lie indiscriminately in the game-bag. The aim of such 
precautions is to avoid misleading records of “straggling.” In this respect 
the diary may prove a useful check on the card-index. 
Mallophaga can be kept either in alcohol or as slides. No card-mounted 
specimen should be tolerated in a collection. Each lot of a species may be 
placed, fully labelled, in a tube 14” x 43,” or x }” as may be required. Hach 
little tube is plugged with cotton wool, and 8-10 may be placed in a squat 
tube 12”x 2”, These larger tubes may be housed, to the number of 8, in a 
glass-stoppered jar 3}”x32”. Such sizes I have found most practically 
useful. Thus a jar of the collection will store from 60-80 lots of parasites, 
any one of which may be expeditiously inspected. The bugbear of corks is 
avoided, and the alcohol may be renewed in one operation. The system is 
also cheap, as 1000 or more insects may be housed permanently for an outlay 
of about 2s. 6d. As to the method of recording—the time-honoured path has 
been followed and stress laid on locality. But in reality the exact locality 
(though not the nature of it) is of secondary importance in elucidating the 
many problems connected with the distribution of these parasites. Zhe area 
of distribution is here no longer a geographical one, but primarily an indwidual 
