I^r THE ANTENNA AND PALPI OF DIPTERA. 



65 



processes, the pits being placed close together. The hairs on the 

 surface are veiy numerous and give a matted appeai'ance. 



Wesche (5) pays great attention to this fly and considers it 

 the most highly sensitive of the Diptera, but with this I do not 

 agree (see above). 



Text-fioure 42. 



Favt of a transverse section of antenna of Gastrnphilus erpii, X 600. 



PUPIPARA. 



HiPPOBOSCiD.E (Text-fig. 43). Ornithomyia avicidaria L. (C. G. 

 Lamb det.) : this species has not the true sense-pit, but slight 

 depressions in the surface with a few thin sensory processes. 



Text-fio-ure43. 



Ch. 



Transverse section of the antenna of Ornitlwmi/ia avicitlaria. X 600. 



Pkoc. Zool. Soc— 1919, No. V. 



