62 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 8o 



does not belong with the anal group attached to the third axillary, 

 but that it is associated with, or attached to, the base of the cubitus. 

 Its relation to the cubitus has been demonstrated by Tillyard (1919), 

 who designates it the second branch of cubitus, and by Karny 

 (1925), who calls it the "cubital sector." In the adult insect, the 

 first vein of the wing, the cos fa (C), when present, usually lies in the 

 anterior margin of the wing. The second vein, the siibcosta (Sc) is 

 associated at its base with the head of the first axillary sclerite (lAx). 

 The third vein, media (M), is usually associated with one or two 

 small median sclcrifcs {m, m') of the wing base. The fourth vein, 

 the cubitus (Cu) has no particular basal connections. The following 

 veins, the anals (A) are definitely attached to the third axillary (sAx) 

 or to an arm of the latter. 



The axillary plates of the wing base play an important part in the 

 mechanism of the wing, for they not only serve to attach the wing to 

 the body, but they determine the efi"ect of the muscles that act upon 

 the base of the wing. Three of these sclerites are almost always 

 present, and have definite relations to one another, to the bases of the 

 veins, and to the adjoining parts of the thorax. The first one, the 

 first axillary, or notopterale, (fig. 27, lAx), is a flat sclerite of the 

 dorsal membrane of the wing base, and is possibly to be regarded as 

 a tergal chitinization. It is hinged by its inner margin to the edge of 

 the tergum, and has its anterior part supported by the anterior notal 

 wing process (ANP). Its anterior extremity is usually more or less 

 closely associated with the base of the subcostal vein (Sc). By its 

 outer margin it articulates along an oblique line with the second 

 axillary. The second axillary, or intraalare (2Ax), has both a dorsal 

 and a ventral surface in the wing base, and may be derived from the 

 proximal end of the radial vein (R), with which it is continuous. 

 By the inner oblique margin of its dorsal part it articulates with the 

 outer edge of the first axillary. Its ventral plate (fig. 30 A, c) has a 

 convex surface that rests upon the wing process of the pleuron when 

 the wing is extended. A tendon-like connection (h) with the subalar 

 sclerite (Sa) below it makes the second axillary the objective of the 

 subalar muscle (F) of the coxa. The third axillary, or hasanale 

 (fig. 27, sAx), though developed mostly in the dorsal membrane of 

 the wing, has also a ventral surface. It articulates with the posterior 

 notal wing process of the tergum (PNP), except when a fourth 

 axillary is present. Its long axis is obliquely transverse, and a lobe 

 on its anterior margin gives attachment to the principal flexor muscle 

 of the wing (fig. 30, A, D) . The bases of the anal veins are associated 



