the Lepidopterous Family Cossidae. 



171 



the base of the first cubital before it coalesces with the 

 fourth median. 



Torlricidae. — At first sight the neuration of the fore-wing 

 of Tortrix, a closed cell from which ten veins arise separ- 

 ately, appears simple and primitive, and in marked con- 

 trast with the more complex neuration of the Cossidae. 

 Nevertheless, if the principles just enunciated are correct, 



Fig. 23. — Tortrix viridana, Linn. 



this simplicity is not primitive but acquired ; it originated 

 from a more complex scheme by a process of loss or astheno- 

 genesis. It needs but little research to confirm the accuracy 

 of this anticipation. In many genera both chorda and 

 median vein are developed, certainly very slenderly but 

 quite distinctly. The areole is usually narrow, the chorda 

 running from a little before 10 to just above 7 in Eucosma, 

 or just opposite 7 in Carpocapsa. The media is unbranched, 



Yig. 24=.— Eucosma variegana, Eb. Fig. 25.— Carpocapsa pomonetta, Linn. 



its exact course through the cell varies, it terminates 

 between 5 and 6 in Eucosma, just opposite 5 in Carpocapsa. 

 The media is more rarely distinguishable in the hind- wing, 

 but a branched media is plainly to be seen in that wing of 

 Isotrias. In this genus the areole is larger than usual, the 

 cho da arising shortly after 11 and ending opposite 6, 

 while the media ends opposite 4. I have not observed a 

 branched media in the fore-wing in any of the Tortricidae 



