BY U. J. TlLLYARD. 



243 



descend upon the apparent meiHan vein, then that vein must be 

 considered to he a pseudo-media. 



The same test cannot, of course, be applied to the pseudo- 

 cubitus, the only sure arbiter in this case being the pupal tra- 

 cheation. It seems, however, inherently probable that the two 

 formations - pseudo-media and pseudo-cubitus— must go together: 

 since, if the true media is displaced and reduced sufficiently to 

 allow of the formation of a pseudo-media, it seems almost essen- 

 tial that the true cubitus must suffer displacement and reduction 

 as well. 



Text-fig.6. — Forewing and basal portion of hindwing of an Apochiysid, 

 OUgochry)<a r/rarilis Esb. -Pet. ,( x -li) for comparison with that of 

 ChrysojM. The median fork (mf) and the limits of Mi and Mj in 

 the forewing cannot be clearly determined. 

 Applying the above rule to the wing of an Apochrysid (Text- 

 fig.6), we see at once that the apparent media must be a pseudo- 

 media. Judged, therefore, on this very important point, the 

 Apochrysidcc. are true allies of the Chrysopidce, and the two 

 groups might perhaps be regarded as subfamilies within the 

 single family Chri/sojjidrp. The ApochrysidcH are in many wavs 

 so highly specialised, that they cannot be regarded as standing 

 anywhere near the direct line of descent of the Chrysopidcr. 

 They stand in the same relationship^ with the Chrysopido' that 

 the genus Psychopsis does to the rest of tlie Osmylidoi. There is, 

 in fact, a very obvious convergence of venational pattern between 

 the Apochrysidfe and Psychopsis. In both, the wing is broad, 



