BY U. J. TILLYARD. 595 



coloured males, perched about a foot apart, and all sitting; in 

 exactly the same attitude, with wings outspread iiorizontally, 

 body held straight out, also Iiorizontally, and at an angle of about 

 60° to the bough. 



In this part of the creek, the rocks were easily lifted and over- 

 turned. At the very first try, I found two full-fed larvaj under a 

 fair-sized rock. The next dozen rocks or so yielded nothing, and 

 then, on a smaller rock, I found a peculiar Aeschnid larva that 

 seemed to be Caliceschna conspersa. Somewhat higher up the 

 creek, under some rocks only hal^-covered by water, I took three 

 more Dip/debia-lsirvse. Having examined some fifty or sixty 

 rocks during the afternoon, I finished up with seventeen Diphlebia 

 larv;¥, all nearly full fed, and four Aeschnid larva;. Besides these, 

 I found two female Diphlebia emerging, and observed no less than 

 three of them ovipositing under the water, just in the same way 

 as I have already described for the female of D. lestoides. The 

 eggs were found in the tissues of the water-weed, and were of the 

 same size and shape as those of D. lestoides already described. I 

 also spent some time looking for young larvae, and found over a 

 dozen, from about 2 to 6 mm. in length, on various rocks. Some 

 of these young larvae were on the same rocks as the full-fed larvae, 

 and I think it is quite likely that the earliest-hatched of the new 

 brood fall victims in large numbers to the rapacity of the later 

 members of the old brood. 



The young larvae were of a pale semitransparent whitish colour, 

 with narrow gills; in appearance, almost exactly like the young 

 larva of D. lestoides figured in my former paper {q.v. p. 376 and 

 fig.4). They were fairly active, running away and hiding in 

 small crevices and depressions in the rocks. Unfortunately it 

 was impossible to keep any of these alive during the long rough 

 journey back to Sydney, so that I was unable to follow up the 

 changes through the different stages of growth. By the time the 

 larva has grown to a considerable size, the colour has become a 

 dark shining greyish-ljlack. I was particularly struck with the 

 helplessness of the larger larvae as soon as they were lifted out of 

 the water. Their huge, cumbersome, caudal gills made it almost 

 impossible fur them to get along, for they stuck to the wet rock, 



