202 



PROCEEDINGS OP THE ACADEMY OF 





Diagram of a wing with two radial arece. 



Veins. 



am. Costal vein or costa. 

 dc. Mediastinal vein. 

 em. Subcostal vein. 

 fg'. Praebrachial vein. 

 gu. Pobrachial vein. 

 hv. Anal vein. 

 iw. Axillary vein. 



xy. Petiole of the radial and cubital veing, or simply petiole, 

 yp. Cubital vein. 



yn and yo radial vein, 'with its two branches, zn the upper, and zo the lower 

 branch. 



d'r. First externoniedial vein. 

 b's. Second externomedial vein. 

 c't. Third externomedial vein. 



Cross-veins. 



b. 

 hi. 



o'. 

 9'h'. 



ff'e'. 

 d'b' 

 b'c', 

 e'f 



vein. J- Discal 

 5-vein. J 



Humeral cross-vein. 



Mediastinal cross-vein. 



Stigmatical cross-vein. 



Central cross-vein. 



Upper discal cross-vein 



First lower discal cross-vein. ss-v( as. 



Second lower discal cross- 

 Great cross-vein. 

 The term central cross-veins has been also used collectively for the whole extent 

 of the veins % y h' g' c' /', or for a part of them, when they form a more or less 

 straight line across the middle of the wing. 



Other terms which have been used. 



x is the origin of the petiole. 



yh' is the portion of the cubital vein anterior to the central cross-vein ; it has 

 itself sometimes the appearance of a cross-vein, being in one line with the 

 central cross-vein. 



7120 is the radial fork. 



oyp is the cubital fork, or simply the fork when it is the only one. 



[Aug. 



