359 
Larva of Chaoborus Crystallinus (de Geer), i 
the sae being “ concertina- wise ” would hardly drag the spots from 
the dorsal to the ventral side. 
Fig. 29. — Gas from posterior sacs has filled one, but has travelled only as far 
as the arrow in the other tracheal tube. Some of the pigment spots from 
the sacs have been carried along and disposed at intervals on the tracheae. 
2 b 2 
