1913] Wing Venation of Fulgoridce. 343 



duction. While the wing venation of most of the insects 

 that have been studied extensively so far can be reduced to a 

 more or less uniform type for the family, in the Fulgoridag 

 no such typical form can be given. In the following discussion 

 of the individual tracheae the differences in the characters of 

 the same trachea in different genera will not be emphasized 

 so much as their resemblances. 



The Costa of the Fore Wing. 

 The costa of the fore wing is usually present in the Ful- 

 goridae, in fact it was found in practically every genus studied. 

 Typically, costa is a single unbranched trachea usually of 

 somewhat less extent than subcosta. In Ormenis (Fig. 3), 

 however, there are many small lateral tracheae formed along 

 the entire length of the costal trachea, and in Amphiscepa 

 (Fig 5), the tip of the costal trachea breaks up into several 

 smaller tracheae. In Thionia (Fig. 27), the costal trachea 

 shows a strong lateral branch near its base. This branch 

 runs parallel with the main branch of costa and seems to be 

 included in the same forming vein. 



The Subcosta of the Fore Wing. 

 The subcosta has been found present in all of the genera 

 studied. In many of the genera subcosta is a larger and 

 more important trachea than radius. In nearly all cases 

 it lies parallel with radius for the greater part of its length, 

 while in Scolops (Fig. 23), it lies parallel with radius for its 

 entire length. Subcosta is typically two branched in the 

 Delphacida (Figs. 43, 45), and in the Cixiida (Fig. 47), while in 

 Amphiscepa (Fig. 5), and Ormenis (Fig. 3), the tip of the sub- 

 costa breaks up into several small tracheae. 



The Radius of the Fore Wing. 

 Radius in the Fulgoridae occupies a much less important 

 position than in the wings of most other insects which have 

 been studied in detail up to the present time. In most cases 

 the radial trachea lies parallel with the subcostal trachea and 

 usually only a single vein is formed in the region occupied by 

 these two tracheae. In Stobcera (Fig. 45), radius is a single 

 unbranched trachea lying parallel with subcosta for more 

 than half of its length then diverging and running parallel 

 with one of the branches of medius for a short distance it 



