284 NEW PERMIAN INSECTS FROM BELMONT, N.S.W., 



Order PROTOMECOPTERA. 

 Family ARCHIPANORPIDAE. 



Aechipanorpa (?) BAIRDAE, ii.sp. (Plate xxsiii., fig. 1.) 



A fragment of a very large wing. Total length 12 mm., greatest breadth 10 

 mm., representing portion of a complete wing probably 30 mm. long. The 

 specimen is cracked obliquely across near the middle, but all the veins are only 

 slightly displaced, and can be followed across the crack. The uppermost vein 

 would appear to be Sc, followed in order by the unbranched Ri, the dichotomi- 

 cally branched Rs, of which eight branches are shown distally, the three-branched 

 M, and finally by Cm, carrying a peculiar closed cell towards its distal end. 

 The manner of branching of the veins, and the system of weak cross-vein struts 

 here and there at irregular intervals, strongly suggests a close resemblance to the 

 Upper Triassic Archipanorpidae ; but there is scarcely enough of this large wing 

 represented to enable it to be placed with any certainty. It might conceivably 

 be a very ancient type of the Order Planipennia. 



Type, Specimen No. P. 1 in Mr. Mitchell's Collection. 



This species is dedicated to Mrs. Pincombe (nee Baird) who discovered it at 

 Belmont. 



It is much to be regretted that this fine wing is not more completely pre- 

 served, so as to allow of a more certain determination of its affinities. 



Order PARAMECOPTERA. 



Family FARABELMONTIIDAE, n. fam. 



Insects having the same general type of venation as Belmontia Till., but 

 with the wings somewhat broader, more rounded apically, Rs and M having 

 six branches each, and Cui without any distal forking. 



The discovery of this new type of wing necessitates a change in the definition 

 of the Order Paramecoptera as originally given by me (These Proceedings, xliv., 

 pt. 2, 1919, p. 234). The portions dealing with Rs, M and Cu should be altered 

 to read as follows : — 



Rs diehotomically branched, with six or more separate branches on the wing- 

 margin. M diehotomically branched, with five or more separate branches on the 

 wing-margin. Cui either simple, as in Mecoptera and Diptera, or having an 

 apical fork, as in Megaloptera, Trichoptera and Lepidoptera; Cu2 a weak, 

 concave, simple vein. 



It will be seen that, by this alteration, the differences between the Parame- 

 coptera and true Mecoptera are considerably narrowed, one of the chief dis- 

 tinctions hitherto having been the presence of the apical fork of Cm in the 

 former Order. However, I think it wise to keep the Paramecoptera as a dis- 

 tinct Order, since it is clear that the general plan of their venation is not truly 

 Mecopterous, but more of the type found in primitive Trichoptera, Lepidoptera 

 and Diptera, though with more branches to both Rs and M. The Parabelmon- 

 tiidae would seem to stand in much the same relationship to the Order Diptera 

 as the Belmontiidae do to the Trichoptera and Lepidoptera. It is evident that, 

 in these generalised types, we have come upon a point in the evolution of the 

 Panorpoid Orders in which the venational differences which later led to the 

 Trichopterous and Lepidopterous types on the one hand, and to the Dipterous 

 type on the other (through the intermediate Order Paratrichoptera) are just 

 beginning to form. If we had the full fossil record, it would be impossible to 



