90 



CAUDAL GILLS OF ZYGOPTERID LARV^, 



their usual positions (as in all functional gills except those of 



Lest idee). 



Text-tig. 22. 

 Ideal (semi-diagrammatiu) T.S. across the Vertical Lamellar Gill-system 

 oi Atifilroayrioii [Afjrionid Form of Gill), to show the internal struc- 

 ture of the gill. Lettering as on p. 109. 

 6. The alveolar raeshwork is reduced, but less so than in the 

 LestidcB', traces of it still existing in the gill-blades as well as in 

 the rachis. 



