DIPTERA. 



361 



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

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

 times, and a cabbage butterfly (Pieris) nine times. The win^^s 

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

 lating the rapidity of the vibrations by the sound produced 



anterior of tlie small basal ceUs ; .1/, third basal cell, or posterior of the smaU 

 basal cells; ^V, anal or axillary corner of the wing; O, alar appendage, (alula). 



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

 u, anterior intercalary. 



Fig. 271 (:?). Wing of Ddsi/pogon. — t, anterior branch of the third longitudinal 

 Tein; u, anterior intercalary vein: r, po.*terior intercalary vein.— From Loew. 



Comparing the wing of Ortalis with that of the bee and butterfly llgiired on 

 page 23, we .should prefer to use the same terniinohjgy and call I, m, n, the margi- 

 nal vein ; A, h, the costal ; c, d and e the tlirce branches of the subcostal vein ; /, the 

 median vein; h, the submedian ; and r, the internal vein. In Macquart's system, 

 modified slightly by Sacken (fig. 270), />, I. is the costal; cw, the subcostal; d and e, 

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



