BT B. J. TILLYATil). 



275 



i'rum the level of the origin of Rs, and 

 then forks again dichotomipally into M, 

 and M2. The lower, M3-4, runs only 

 about half the distance of the upper, 

 and then forks uniserially, M3 continu- 

 ing the line of M3-4, while M4 diverges 

 sharply posteriad for a short distance, 

 until it meets a longitudinal branch from 

 Cui (m-cti) ; it then turns distad so as 

 to continue the line of m-cu. From this 

 point on, the wing is divided evenly by 

 the series of very slightly diverging 

 veins Mi, M2, Ms and M4, with the 

 branches of Rs continuing the series an- 

 teriorly, and the branches of Cui pos- 

 teriorly. Distance between fork of 

 Mi-2 and fork of M3-4, 2.5 mm.; length 

 of basal piece of M4, 1.2 mm. The 

 medio-cubital cell is closed basally by a 

 short weak cross-vein descending from 

 R-)-M on to the very weakly formed 

 main stem of Cu (both of these being 

 barely visible), and ends distally at the 

 basal piece of M4. Within it is to be 

 seen the peculiar and very irregular 

 formation of veinlets shown in Text- 

 fig. 67. These consist of a fairly 

 strongly marked curved longitudinal 

 vein running from Cui very close to 

 the base to join Ms -4 slightly distad 

 from its origin. This vein is divided, 

 just before half-way, by a transverse 

 vein above it, which forms the distal 

 boundary of a small closed cell lying 

 just below M, and connected with it by 

 two very short and weak cross-veins; 

 the small cell is completed by a convex 

 vein above, arising from the long vein 

 already mentioned at a point slightly 

 distad from its origin. Below this 

 small cell are two oblique cross-veins, 

 weakly formed, with a third similar 

 cross-vein descending from the long 

 vein on to m-cii just distad from them. 

 This peculiar formation should be com- 

 pared with the simpler rormatiou to he 

 met with in the same area of M. ajfine, 

 n.sp. 

 The very weakly formed basal piece of Cu forks quite close to the base 

 into Cui and Cu2 (Text-flg. 67), both of these being weakly indicated for a 

 short distance, until they are connected by a weak cross-vein. Beyond that point, 

 they begin to strengthen, Cui soon becoming a very strong convex vein, which 



Text-fig. 66. 



Mesogereon superbmn , n.sp. 

 Venation of forewing. (x 3|^). 



