THE WINGS OF SYMPHEROBIIDJE 



179 



several genera that do not exhibit the method of speciaHzation of the wings 

 that is distinctively characteristic of the Hemerobiidac, but on the other 

 hand exhibit a type of specialization distinctively characteristic of this 

 group of genera. To this group belong the American genera Sympherohius 

 and Psectra, the genus Amiandalia from Calcutta, and the Australian genus 

 Notiobiella. I suggest that these genera and such other genera as may be 

 found to exhibit the same type of specialization of the wings be grouped in 

 a separate family to be known as the S\-mpherobiida3. 



Wings of Sympherohius amiculiis. 



The distinctive characteristic of the Sympherobiidee is that vein R2+3 

 of the fore wings has become separated from the remainder of the radial 

 sector and is attached separately to vein Ri. This results in the radius of 

 the fore wing having two sectors each of which is forked (Fig. 173). 



In each case where this switching of the base of vein R2+3 from the 

 stem of the pectinate radial sector to vein Ri has occurred there is a cross- 

 vein extending from vein R2+3 to the stem of the radial sector. It is 

 probable that the switching occurred by the way of this cross-vein-, and 

 that after vein Ri was reached by vein R.j+3 the base of the latter vein 

 migrated a short distance towards the base of the wing. 



