450 Scientific Proceedings, Royal Dublin Society. 
A striking fact in the distribution of the Corduliine is their 
comparative scarcity in the NrorropicAL Rreeion. Only four 
genera, three of which are peculiar, out of the twenty-three 
included in the sub-family, occur in the region, and none of the 
species are found in Central America or in the West Indies. The 
Sonoran Recion has seven “genera, of which two (Hpicordulia 
and Didymops) are peculiar; and two others (Newrocordulia and 
Tetragoneuria), though they evidently range into the Canadian 
sub-region, may be fairly reckoned as Sonoran, the bulk of their 
species being southern. Excluding the Sonoran stragglers just 
mentioned, the Honarcric REeeion is seen to be entitled to six 
genera, of which three are peculiar. Owxygastra is Huropean and 
Mediterranean, and Epitheca European and Siberian, while Cor- 
dulia is Kuropean, Mediterranean, Siberian, and Canadian. The 
Evuiop1an Recion, like the Neotropical, is poor in Corduliinee, 
possessing only four genera. Two of these, Neophya and Pseudo- — 
gomphus, are peculiar; a third, Phyllomacromia, has three species 
in Africa, and one in Madagascar. The Mascarnne Reeron has 
two other genera, of which one, Jesocordulia, is confined to 
Madagascar, while the other (Hemicordulia) is Mascarene, Oriental, 
and Australian. Five genera are found in the Orrenrat Rueion, 
but only one, Idionyx, is peculiar. It is noteworthy that the 
Indo-Malayan sub-region has all five of the genera, the Indo- 
Chinese three, and Hindustan only two. The AvusrraLian 
Reeton has six genera, four of which (Cordulephya, Pentathemis, 
Syncordulia, and Synthemis) are confined to it; it is noteworthy that 
only the last of these four ranges beyond the Australian continent. 
Nineteen of the twenty-three genera of Corduliine are thus 
seen to be practically confined to one or other of the various 
regions, a very high degree of faunistic specialisation. The 
remaining four genera exhibit distributions of considerable interest. 
Hemicordulia has most of its species in Australia and Polynesia, 
one species in Celebes (which we reckon as belonging to the Indo- 
Malayan sub-region of the Oriental), one in the Khasia Hills, one 
in Madagascar, and one in Mauritius. Such discontinuous range, 
and particularly the almost total absence of the genus from the ~ 
Asiatic continent suggests an ancient and decadent group. 
The distribution of Somatochlora is very suggestive. The 
—a_ = Ss Ll OTe 
