572 JOORNAL, BOMBAY NATURAL HISTORY SOCIETY, Vol. XVI. 



In the forewing there is a central more or less triangular cell, the 

 sides of which are known as the upper, lower and outer margin (or 

 transverse vein) respectively. 



There is one vein rising free from the cell below it (No. 1) and one 

 free above it (No. 12) and 10 veins numbered 2 to 11 rising out of 

 the cell. 



The hindwing is similar, except that there are only six veins rising- 

 out of the cell and consequently the upper one is numbered 8 instead 

 of 12, and. there are two free veins below the cell numbered la and lb. 

 At the base of vein 8 there is a short vein running to the costa known as 

 the " precostal spur ' ! which is sometimes forked and sometimes 

 obsolete. 



--(■he precosfal spur 



It will be as well to remember the technical terms for some of the 

 commonest variations : 



If 2 veins instead, of rising independently have a common origin 

 from the cell and branch apart later, they are said to be " stalked." 



If 2 veins rise independently and after coalesce for a short distance 

 and then separate again they are said to " anastomose. " An extreme 



