132 FOSSIL INSECTS FROM COM M ENTRY, FRANCE, 



Amber. This insect belongs to the Order Psocoptera or Copeo- 

 gnatha, an Order which is not Holometabolous, but which pos- 

 sesses a reduced venation very closely resembling that of certain 

 Holometabolous Orders, in particular the Hymenoptera. Nearly 

 all recent Psocoptera have a much more specialised venation than 

 Amphit^nfomum; but close relatives of the latter still exist in the 

 peculiar genera Echmepteryx and Ci/mafopsocus, as well as the 

 genus Amj)hi('7ifo7num itself, which has recently been rediscovered 

 in Ceylon. 



It will be seen that the correspondence between the wing-veins 

 of Sycopteroii and Ar)ip)hiento7nuin is exceedingly close; in fact, 

 they can be completely homologised, provided only that Sycopf- 

 eron possesses the short basal piece of Rs which is absent from 

 Bolton's figure. A close examination of the photograph of 

 Sycopteron, in Bolton's PI, ii., fig. 1, suggests to me that this piece 

 actually does exist; at any rate, it seems to be clearly indicated 

 on the left wing. The fossil should certainly be further examined 

 to determine this point. 



In Am^jhifiitoiHum, the subcosta is a very weak vein, merging 

 into the costa before halfway. The radius is a strong vein, forked 

 distally, and giving off its sector far distally, at a point only just 

 before its fork. Rs itself is forked, as in Sycopteron (the vein 

 Bolton calls R). Further, M is three-branched in Am^Dhientomum, 

 in the same manner as in Sycopte7-on (the vein Bolton calls Rs). 

 In Amphimfom^im, the cubitus is forked far distad, and is 

 attached to the stem of M at a point quite one-third of the wing- 

 length from the base; in Sycoptero7i, the attachment and forking 

 lie both much further basad. So also the anal veins in Amphi- 

 entomum are less primitive than in Sycopteron, being shorter and 

 less straight. 



Now Amj^hientomum is evidently specialised in the following 

 points : — 



(1) The shortening of Sc. 



(2) The removal of the origin of Rs far distad, and consequent 

 shortening of that vein. 



(3) The close union basally between M and Cu. 



