INTRODUCTORY NOTE 
T he six species of parasitic Diptera in our collection were all obtained in 
the Patani States by Mr. Robinson and myself, and Dr. Speiser tells 
me that they are the first recorded from the Malay Peninsula. From 
a morphological standpoint, the chief interest of the collection lies in the 
inclusion of a species of the anomalous genus Ascodipteron^ on the anatomy of 
which we hope that the same author will furnish us a paper later. From a 
purely bionomical point of view, the specimens of the other species enumerated 
and described would seem to indicate a difference of habits between the 
Nycteribiidae and the Streblidae^ for the two species representing the. former 
family were taken in different localities, each on a specific host ; while each of 
the two species of Streblidae was taken on two different hosts not even belonging 
to the same genus. Pteropus vampyrus and Scotophilus castaneus^ however, are both 
bats which sleep during the day apart from other species, in trees, or in the 
roofs of houses in the case of the latter ; but the bats on which we took 
specimens of the Streblidae probably lived in caves, together with an enormous 
number of other individuals belonging to a great variety of species ; and even 
the wingless Diptera pupipara^ with the exception of such forms as Ascodipteron^ 
are sufficiently active to make their way from one host to another. It is 
interesting also to notice that the Dipterous parasite of Pteropus vampyrus is 
almost as much larger than that of any other bat which we saw, as Pteropus itself is 
than any other Cheiropterous host ; Ascodipteron must again be excepted, but 
when parasitism has produced such extreme changes as it appears to have done 
in this animal, we must always look for increase of bulk. 
NELSON ANNANDALE 
Q 
24/8/03 
