WING-VENATION OF THE PLECTOPTEEA. 
145 
purposes of comparison the fore-wing of Ameletus ornatus is placed on p. 146 
(text-fig. Ih). The corresponding notations of Comstock-Needham and 
Morgan are given in the accompanying table. In the second column the 
alternate convexity and concavity of these veins is indicated by the signs 
-I- and — . 
Text-fig. 1 a. 
1^ lAx lAi Cu, Caic Caii <^^i: 
Hind-wing ol" Protereisina sp., Lower Permian of Kansas ; the fore-wing is closely similar, but a little 
narrower at base, as sbown in text-fig. 3. 
Table oi' Wing- Venation or Matplies. 
New Notation. 
Sign. 
Comstock-Needbam 
Notation. 
Morgan's Notation. 

4- 
C 
C 
Sc 
— 
Sc 
So 
El 
+ 
Ri 
R, 
IRsa 
— 
R, 
Ml 
2R,a 
-1- 
(omitted) 
(omitted) 
SRoa 
— 
(omitted) 
(omitted) 
4Rja 
+ 
(omitted) 
(omitted) 
- 5Rja 
- 
Rs 
Rs 
Rab 
+ 
R,, 
Interpolated vein 1. 
Ra 
— 
R5 
Mo 
E4a 
+ 
Ml 
M3 
Rib 
— 
M. 
(omitted) 
Rs 
+ 
Ma 
M4 
Ml 
— 
Cui 
Cui 
M, 
-1- 
Interpolated vein. 
Interpolated vein. 
M3+1 
- 
Cu, 
CU2 
Cui 
+ 
lA 
lA 
Cu. 
— 
2A 
2A 
lA 
-1- 
3A 
3A 
2A 
+ 
3A 
3A 
3A 
+ 
3A 
3 A 
10* 
