OLFACTORY ORGANS OF FLY. 53 



them, and it appears to be really a sac lined with sense- 

 hairs. 



Hicks* described the structure of the antennse in a 



Fig. 40.— Antenna of blowfly (after Hicks), a, EnTarped third segment, showing 

 pits ; c, base of the antenna. 



considerable number of insects. On the antenna of the 

 blowfly (Musca ; Fig. 40) he found no less than 17,000 

 perforations, each leading into a small sac, besides which 



* Transactions of the linnean Society, 1857-1859. 



