BIPTERA. 



361 



M. Marey has determined that a common fly when held cap- 

 tive moves its Avings 330 times a second ; a honey bee 190 

 times, and a cabbage butterfly (Pieris) nine times. The wings 

 describe a figure 8 in the air. (Cosmos.) Landois, calcu- 

 lating the rapidity of the vibrations by the sound produced 



anterior of the small basal cells; M, third basal cell, or posterior of the smaU 

 basal cells; N, aual or axillary comer of the wiug; O, alar appendage, (alula). 



Fig. 271 (2). Wing of Empis. — t, anterior branch of the third longitudinal vein; 

 M, anterior intercalary. 



Fig. 271. 



Fig. 271 (3). Wing of Dasypogon. — t, anterior branch of tlie thir<l longitudinal 

 vein; u, anterior intercalary vein; r, posterior intercalary vein. — From Loew. 



Comparing the wing of Ortalis with that of the l)ee and butterlly figured on 

 page 23, we sliould prefer to use the same termiuology and call I, m, n, the margi- 

 nal vein ; A,h, the costal ; c, (/ and e the tln-ee branclies of the subcostal vein ; /, the 

 median vein ; h, the Submedian ; and r, the intei-nal vein. In Macquart's system, 

 modified slightly by Sacken (fig. 270), h, I, is the costal; cm, the subcostal; d and e, 

 the median; /, the submedian, and g tlie internal vein. 



