JAPANESE DRAGONFLIES OF THE FAMILY CALOPTERYGIDAE. 151 
must include the Bonin Islands in the region to which Loo-Choo and Formosa 
belong. 
The Kurile Islands and Saghalin can be disregarded in considering the 
distribution of Calopterygidae, since no single specimen has been obtained 
from those regions. 
I wish to express my sincerest thanks to Prof. Dr. M. Matsumura 
fir his constant aid and kind advices dnring my study on odonatology. My 
obligations are also due to Messers Uchida, Fukuda, Yaxo and IvOMURA 
for their kindness in putting their collections at my disposal. 
Key to the Japanese Calopterygidae. 
A Wings longer than abdomen, frons projected forming a large tubercle. 
B Mi -3 and M 4 arising from a single point on the Ar. ... Micrvmerus. 
BB M,_. and M, widely apart in the start Rhynocypha. 
AA Wings shorter than abdomen, frons not projected. 
B Bod y stout, with tiic coloration of a Gomphus Palaeophlebia. 
BB Body slender like an Agrionid. 
C Subquadrangle slightly bent at the arculus, M w arising from the middle 
or upper part of the latter. 
D Quadrangle and basal radial space crossed Euphaea. 
DD Quadrangle and basal radial space free from cross nervures Bayadera 
CC Subquadrangle nearly straight, M l s and M 4 arising from the lower part 
of the arculus. 
D True pterostigma present. 
E Quadrangle with 10 or more cross nervures Psolodesmus. 
EE Quadrangle Avith only 4 or 5 cross nervures Mnais. 
DD True pterostigma obsent. 
E M i and M ; j bifurcated Kevrobasis. 
EE M* and M 3 simple. 
F Basal space reticulated Mairona. 
FF Basal space free from cross nervuress Calopteryx. 
