MECOPTEROID GROUPS 85 



of smaller groups, many of them of very uncertain affinities, 

 which have been given ordinal rank by Handlirsch. For the most 

 part they are based upon anomalous fossil remains, usually few 

 in number, which have been made the types of provisional orders 

 more especially to emphasise their essential differences as compared 

 with other groups of insects. The orders Paramecoptera, Para- 

 trichoptera and Protodiptera of Tillyard are also only doubtfully 

 separate and distinct. No parts other than wings have so far 

 been discovered, and from their venational characters it is presumed 

 that their nearest living relatives are the Mecoptera. In his 

 later communications Tillyard (1935, 1937) regards them as being 

 sub-orders of this originally extensive order (the Mecoptera). 

 They are all characterised by a primitive venation, which was 

 essentially similar in both fore and hind wings, and by the single- 

 branched Cu^. 



The Paramecoptera are represented by the genera Belmontia 

 Till, and Parahelmontia Till, from the Upper Permian of Belmont, 

 N.S.W. They are characterised by the rather extensive dichotomy 

 of Rs and M, and in Belmontia there is a short distal fork to Cu^. 

 In so far as the last-named genus is concerned, its features betray 

 no insuperable barrier to its being regarded as a remnant of a. 

 group which was ancestral to the Trichoptera and Lepidoptera. 



The Paratrichoptera are characterised by both Rs and M 

 having four branches only, arranged dichotomously. They 

 comprise Mesopsyche Till., Neuropsyche Till., Aristopsyche Till., 

 and Triassopsyche Till., from the Upper Trias of Queensland : 

 Pseudopolycentropus Handl., Lias of Europe and LiassopMla 

 Till., Upper Lias of England. 



The Protodiptera are based upon a dipterous type of wing to 

 which Tillyard (1929) gave the name of Permotipula. This 

 discovery was followed several years later by the finding of a 

 four-winged insect with very similar venation in both pairs of 

 wings (Tillyard, 1937). Both these fossils were found in Upper 

 Permian rocks of Warner's Bay, New South Wales. The second 

 example is clearly that of a four-winged insect whose wings are 

 of a type still to be found in the most primitive living families of 

 Diptera. The wings bear a marked dipterous facies in their 



