ON THE LIFE-HISTORY OF THE DRAGONFLY. 



439 



AVES. 



2 Somali Ostriches {Struthio molyhdophanes), purchased on 

 May 8th. 



2 White Rheas [Rhea americana), purchased on May 12th. 

 1 Kagu [Rhinochcetus juhatits), from New Caledonia, purchased 

 on May 4th. 



4 Long-tailed Shrikes [Urolestes melanoleucus) and 1 Black- 

 collared Barbet (Lyhius torquatus), from South Africa, deposited 

 on May 22nd. New to the Collection. 



4 Isabelline Turtle-Doves {Turtur isabellma), 2 Rosy-grey 

 Turtle-Doves (Turtar roseigriseus), 6 Dongola Turtle-Doves 

 {Turtur decijnens), from ISTorth-East Africa, deposited on May 1st, 

 and 2 Spotted-bellied Francolins {Francolinns spilogaster), pre- 

 sented by Major Maurice Portal, P'.Z.S., on May 1st. All new 

 to the Collection. 



Reptilia. 



1 Siamese Crocodile (Crocodilas siamensis) and 2 Tentacled 

 Snakes {Her2:>eioii teyitacidatum) from Siam, the latter new to the 

 Collection, presented by Dr. Malcolm Smith, F.Z.S. 



Prof. J. E. DuERUEX, F.Z.S. . exhibited and made remaiks upon 

 a series of Ostrich eags. 



Dr. R. J. Tillyard, M.A., D.Sc, F.L.S., F.E.S., gave an 

 account, illustrated by lantern-slides, of The Life-history of the 

 DragonHy, v/ith special reference to Australian forms Dr. 

 Tillyard dealt first with the structure of the female ovipositor, 

 a.nd showed the correlation between the habit of laying e<.'gs in 

 the tissues of plants and the elongated form of the eggs, on the 

 one lianrl, and that of laying them freely in the water, the eggs 

 in this case being of a much more rounded form, 'i he develop- 

 ment of the embryo and the hatching of the larva were next 

 dealt with ; the crea.ture that batches from the egg is not an 

 active larva, but a sheathed pronymph, Avhose existence lasts but 

 a few seconds, and from which the active young larva emerges in 

 its turn, representing actually the second larval instar of other 

 insects. The various types of larvre found in the two suborders 

 Anisoptera and Zygoptera w*:>re next shown, and a series of 

 slides dealt with the interesting larval specialisations in the 

 gizzard, the prehensile labial mask, and the rectal and caudal 

 gills. 



