36 



Bulletin No. 159 



'4-pif.l 



V\)> 



Fig. 17. — Ventral view of head and mouth-parts of yellow fever mosquito larva, a, head; 

 fi, antenna; r, mandibles; d, labium. 



Fig. 18.— Vibratile hairs from mouth of yellow fever mosquito larva. 



TIPULID>e (CRANE FLIES). 



In the spring-fed rivulets flov^ing down the banks of 

 the Left Fork of Straight Creek, I took October 21, 1911, a 

 number of the leathery larvse belonging to this group. None 

 of the adults are known to sting, and excepting as they are 

 sometimes attracted to lights are not often seen about 

 dwellings. Larvse of terrestrial species are often found 

 in large numbers about decaying vegetable matter on lawns, 



