H. Scott 
595 
of the small insect-eating Vespertilionidae, and also from the Nycterid 
bat Megaderma lyra, which eats small Vertebrates. This last is one of 
the cases in which the hosts belong to more than one family. It is 
shown in a table which I drew up for some Ceylonese Nycteribiidae 
(1914o, p. 212). The same table includes another such case, that of the 
wide-spread Eucampsipodia hyrtli, which has been recorded from several 
species of the fruit-eating genus Rousettus (evidently its normal hosts), 
and also in a solitary instance from the Vespertilionid Tylonycteris 
pachypus. Penicillidia dufouri is known from both Rhinolophidae and 
Vespertilionidae (Speiser, 1901, p. 50), both of which families, however, 
belong to the insectivorous category. The insects’ powers of selection 
of hosts seem fairly elastic. 
(ii) Conversely, as stated above, one species of bat may harbour 
several kinds of Nycteribiidae. At least 9 species have been recorded 
from Miniopterus schreibersi in various parts of its wide range. Atten¬ 
tion has previously been called to the fact that examples of several 
species and genera of Nycteribiids may be found on the same indivi¬ 
dual hat (Scott, Nycteribiidae from Formosa, 1908, p. 359, and 1913, p. 93). 
In this connection the habits of the bats must be taken into considera¬ 
tion. So far as known, the insects leave the bats only rarely and for 
short intervals (see below), therefore their chances of infesting several 
species of bats must depend on the extent to which these come in con¬ 
tact with one another. The big flying-foxes of the genus Pteropus, which 
eat fruit, rest, as far as I know, not in caves or buildings, but hanging from 
branches of trees, and consort in great numbers in particular places (called 
“camps” in Seychelles). Such bats are not likely to come into contact 
with bats of other families and genera: as far as I am aware, no Nycteri¬ 
biidae have been found on them except certain large species of Cyclopodia, 
which, conversely, have not been taken from bats of any other genus. 
On the other hand the vast majority of the Formosan Nycteribiids 
referred to above were obtained from large numbers of Miniopterus 
schreibersi congregated in an old temple. Isolated individuals of two 
other bats, a Myotis and a Pipistrellus, hung among the Miniopterus ; 
the parasites could easily wander from one species to another, and some 
specimens were collected from Myotis and Pipistrellus, though the 
collector (Hans Sauter) stated that when these latter were captured alone, 
they were usually quite free from Nycteribiids. Perhaps some kinds of 
bats are constitutionally less liable than others to become infested, even 
though they may be equally accessible to the parasites. Somewhat in con¬ 
trast to the Formosan case is that of 5 species of Nycteribiidae collected 
Parasitology ix. 39 
