432 MESOZOIC INSECTS OF QUEENSLAND, iii., 



(5). In the above compaiison, due allowance must be made for 

 reduction of the original venation, owing to the extreme narrow- 

 ing of the wing. 



Taking, then, the Mecopteran characters first, it will be seen 

 that these may be practically summed up in the dichotomous 

 nature of the branchings of the media. But, in the Mecoptera, 

 the radial sector undergoes a similar series of dichotomous 

 branchings. We must assume, then, that this type of branching 

 is not in itself evidence of Mecopteran affinities, unless accom- 

 panied by other definite characters. That this is certainly so is 

 shown by the 'Avchsiic Pf^i/chopsis illidypi, which belongs to the 

 Planipennia, but which has, nevertheless, a media dichotomously 

 branched, in a manner not unlike that of the fossil. 



The Planipennian affinities suggested are the general appearance 

 of the wings as being those of a "lacewing," with their numerous 

 parallel longitudinal veins supported by, for the most part, 

 delicately formed cross- veins; the great strength of tlie radius, 

 and the close, parallel situation of the subcosta in a deep groove 

 in front of it; and also the correspondence between the branch- 

 ings of M in the fossil and in Psychopds il/idgei, already men- 

 tioned . 



The principal characteristic of all known Planipennia, however, 

 is the large number of descending branches of the radial sector. 

 It is these veins that form, in this Order, the majority of the 

 parallel longitudinal or oblique veins traversing the wing. But, 

 in the fossil, Rs is unbranched. This alone seems quite sufficient 

 to prevent us placing the fossil within the Planipennia. Further, 

 in all archaic Planipennia, the series of cross- veins between C and 

 Sc is oblique; whereas, in the fossil, those that can be seen are 

 at right angles to the main veins, as in Odonata and Protodonata. 



A further argument against both Mecopteran and Planipennian 

 affinities for this fossil is the absence of any signs of macrotrichia 

 upon the main veins. Even the strongly built radius, which is 

 exceptionally well preserved, shows no signs whatever of having 

 carried these structures. 



The Odonata themselves cannot be brought into consideration. 



