440 NEW AND RARE AUSTRALIAN AGRIONID^, 



The whole of the rock is densely covered with ferns. Rest- 

 ing on these ferns, deep in shade, and drenched with the 

 spray of the fall, I found this little dragonfly. I netted one 

 or two after disturbing them, but most of the specimens were 

 just picked up by the fingers. They were very inert, but, 

 as it was a very rainy day, they probably are not always so. 

 Altogether, I took about fifteen males and two females. The 

 locality was, to my mind, very much like that in which, 

 later on, I discovered Argiolestes fontanus at Dorrigo, 

 N.S.W. I think that these tiny waterfalls, in dense tropical 

 forest or scrub, are the rendezvous of several rare and re- 

 tiring species. At midday, the almost vertical sun lights up 

 the little open space in front of the fall, and here, doubtless, 

 these dragonflies collect to disport themselves, and to find 

 their mates, retiring to rest on the fern fronds when the sky 

 is overcast. 



General Note on the Australian Species of the Legion 

 Protoneura. — De Selys knew of only one Australian species 

 of this legion, viz., Nososticta solida (1860). Over forty 

 years elapsed before another was added, Isosticta simplex, by 

 Martin (1901). From 1905 to the present time, I have 

 been fortunate to discover no less than six more ; but even 

 now, these eight form a very small proportion of the number 

 described altogether, which is, I believe, more than a hun- 

 dred. Apart from the Australian representatives, the group 

 appears to be a tropical one, extending throughout the Tor- 

 rid Zone ; so that we may consider the Australian portion 

 to be a tropical invasion from the region of New Guinea 

 and the Torres Straits Islands, the invaders having probably 

 themselves been descended from an older stock inhabiting 

 Ceylon, Java, and the Celebes, which gradually worked east- 

 wards. We have strong evidence for this theory in a com- 

 parison of the Australian forms with the Indo-Malayan 



