Rev. F. D. Morice's Notes on Australian Sawjlies. 325 



(b) Venation of the hind-wing. — In most Arctogaeic 

 genera a " cubital " and also a " recurrent " nerve are 

 present in the hind-wing, and the former lies beyond the 

 latter (i. e. approaches nearer to the apex of the wing), 

 so that two "enclosed cells " appeal', of which the upper 

 one is larger than the lower. More rarely the recurrent 

 nerve only is present ; and in some cases both nerves are 

 wanting, so that the wing has no enclosed cells at all. 



In Australia all indigenous genera except two out of its 

 three Arginae, viz. Trichorhachus and Antargidium, have 

 the cubital nerve present, and the recurrent absent— the 

 one state of things which, if I mistake not. is never to be 

 found in Arctogaeic forms. And both Trichorhachus and. 

 Antargidium differ from very nearly all Arctogaeic genera, 

 even from their nearest relations among the Arginae, in 

 that, though a cubital and a recurrent nerve are present, 

 the former never lies beyond the latter, but (vice versa) the 

 recurrent nerve in Trichorhachus lies far beyond the cubital, 

 making the upper of the two " cells " by far the smaller !, 

 while in Antargidium the two nerves are practically inter- 

 stitial, and the " cells " are approximately equal. I had 

 almost said that no Arctogaeic genus had a similar venation, 

 but I should have been wrong, for one has it, viz. Aihalia ! 

 There, too, the nerves are interstitial, and the two cells 

 approximately equal. Of the Neogaeic genera Syzygonia 

 and Incalia only seem to have a Notogaeic type of neura- 

 tion in the hind-wing. In other cases two closed cells are 

 regularly present, and these have the shapes and proportions 

 usual in Arctogaeic forms. 



(c) Antennae. — The type of antenna which is beyond 

 all comparison the most usual in Arctogaeic Snwflies — 

 namely, nine nearly simple cylindrical joints, generally 

 tapering slightly from the base to the apex, none of them 

 showing any very noticeable tendency to swell out or 

 project at its apex and so give the antenna a " serrate," 

 " moniliate," or "pectinate" appearance — seems to be 

 entirely unrepresented in Australia. Instead, we find 

 there all the Tenthredinid genera furnished with antennae 

 more or less resembling those of some or other Arcto- 

 gaeic, but not specially Arctogaeic, group. Zenarge and 

 Antargidium have them much as in Arge; Trichorhachus 

 as in Schizocera ; Perga and Xyloperga as in Cimbex or 

 more often as in Abia; Pterygophorus and Polyclonus sa 

 in certain Lophyrinae] and both sexes of several genera as 



