Carpenrer— The Geographical Distribution of Dragonflies. 441 
sition Zone. Dragonflies are naturally apt to spread widely, and 
_ it is appropriate to consider a genus peculiar to a region when it 
only transgresses the frontiers for a short distance or, if a large 
genus, with but one or two species. 
The Manchurian sub-region of the Holarctic has a large 
Oriental element in its dragonflies ; indeed it is to some extent a 
transition zone between the two faunas. In dealing with the 
Malayan sub-regions I have regarded Celebes as Oriental ; its 
dragonflies seem to show more Oriental than Australian affinities. 
There is, however, much similarity between the Oriental and 
Australian dragonflies, a number of characteristically Oriental 
forms range into Papua and even into Australia and Polynesia. 
The distribution of the genera of each sub-family is shown in 
the following tables. The figure after each genus indicates the 
total number of known species, and the figures in the columns 
show the number of species found in each sub-region. By this 
means it is seen at a glance how widely each genus ranges, and 
in what districts it is most abundantly represented. At the end 
of the tabular view of the distribution of each sub-family I have 
pointed out what genera occur in or are peculiar to the various 
regions. 
A short summary of the distribution of dragonflies, compiled 
from tables furnished by M. R. Martin, is to be found in Dr. 
Trouessart’s excellent little book! on geographical distribution. It 
- will be seen that the statements there made regarding the absence 
xo. 
nny 
i 
of certain sub-families from various districts require modification. 
The Agrionines (Calopterygine) are represented in Madagascar 
(though only by one species) as well as in Papua. Libellulines 
occur both in New Zealand and Polynesia, and Auschnines in 
Polynesia and Madagascar. 
1“ La Geographie Zoologique,’’ (pp. 275-6.) Paris, 1890. 
212 
