DESCEIPTIONS OF AUSTRALIAN ^SCHNIN^. 25 



in Plate 1. fig. 2.) Arriving here about 4.30 p.m. each day, I waited 

 patiently for the arrival of my Dragonfly. Facing up the stream, I com- 

 manded an uninterrupted view of between fifty and a hundred yards of the 

 creek-bed, which was very narrow, shallow, and closed in by palms, ferns, 

 and trees. At the top end was a low ledge of rocks and a small pool. Over 

 this ledge of rocks the Dragonfly would drop swiftly in ghost-like fashion, 

 its remarkable coloration making it almost invisible except as a diffused and 

 rapidly moving blurr. Again and again I saw the insect appear thus far 

 ahead of me, only to realize that it had passed me before I could strike. Its 

 speed must have been quite equal to that of a Macronia, generally admitted 

 to be the swiftest of all Dragonflies. In a day or two I got more used to the 

 habits of the species, and at last captured a fine male as it careered past me. 

 The next day I repeated the performance, and at the end of three weeks I 

 had six tine males to my credit. Females were obtained by beating clumps 

 of tree-ferns towards evening, when they would fly wildly out and occasion- 

 ally return after careering about for a few minutes : of them I captured four 

 altogether. 



A half-grown larva was taken alive under one of the flat rocks in the bed 

 of the small creek shown in Plate 1. fig. 2, while a male larval skin was 

 taken on some native arums at the back of the large pool shown in Plate 1. 

 fig. 1. In the afternoons, when parties of visitors were bathing in this pool, 

 A. costalis used to appear suddenly and career with lightning speed around. 

 It was here that I once saw a pair in co])., and noticed that the male occa- 

 sionally accompanies the female while ovipositing. But it is more usual for 

 the female to oviposit by herself. This is done towards evening, or, in dull 

 days and in deep secluded parts of the creeks, perhaps earlier. The female 

 flies more slowly than the male, examining carefully all the ins and outs of 

 every little pool, and pausing at every fancied spot. Every now and then 

 she would half-settle with quivering wings on some small log or stick, and, 

 inserting her abdomen into the water, place one or two eggs into the sub- 

 merged tissue of the wood. This was done by a quick to-and-fro movement 

 first of all, which I have no doubt was a sawing or rasping of the wood by 

 the projecting teeth of segment 10 ; then the abdomen would be curled up 

 somewhat, and pressed downwards two or three times into the water. This 

 latter movement was clearly the actual placing of the eggs in the newly- 

 opened wood-tissues. 



A few notes which I made conceruino- the remarkable flight of this insect 

 may be of interest. First, as to its speed. It is notoriously difficult to 

 judge the speed of a small object, but I made one or two iittempts to do so. 

 The distance from niy watchiug-place, in the foreground of Plate 1. fig. 2, 

 to the ledge of rock over which the swift-flying males first appeared was, as 

 near as I cotild judge, about eighty yards. From the time they first appeared 

 to the time they passed me was barely sufficient for me to grip my net and 



