IN THE LAEV^. OF ANISOPTERID DRAGONFLIES. 



157 



[2 B. Papillo-Foliate Sub-type. (Text-fios. 9-10 ; Plate 19. figs. 7-8 ; 



Plate 21. figs. 16, 19.) 

 The very remarkable form of foliate gill-type found in Anaa^ has been 

 studied by Dufour, Oustalet, and others. All of these authors up to 

 Poletaiew believed that this type of gill belonged to the genus ^mdina, but 

 none of them attempted to breed out the larva which they were studying. 

 Poletaiew, who studied undoubted larvse of ^^scJma, failed to find the 



Text-fig. 9. — Anax papuensis, 

 Burm. 

 Three complete hemibranchs from 

 the everted gill-basket of a full- 

 grown larva. Pcqnllo-foliate. Sub- 

 type. Semi-diasrammatic, drawn 

 from a whole mount. ( X 40.) 



Tp:xt-fig. 10. — Anax papuends^ 

 Burm. 

 A single papilla from the same larva. 

 (x360.) h, base; ch, chitinous 

 hooks; ^7(/, pigmented epithelium 

 of the basal hump ; tl, loops of 

 ti'acheal capillaries. 



papillae mentioned by these earlier authors. She therefore questioned the 

 accuracy of their descriptions, but failed to discern the true cause of the dis- 

 crepancy. It remained, then^ for Ris to show that the truly 'pa'pillo-foliate 

 gill belonged to the genus Anax. My own studies of this type have been 

 carried out on the larva of Anax papuensis. 



The structure of the separate leaves in Anax is very easily understood, in 

 spite of their complexity. Each leaf, instead of being of the crinkly cabbage- 



