322 Rev. F. D. Morice's Notes on Australian Saw/lies. 



Australia. For they can include no forms but such as have 

 succeeded in maintaining themselves while passing gradually 

 southwards through climates and surroundings which 

 differed at every stage in the journey, and as have found 

 everywhere a vegetation suitable for their ovipositions. and 

 held their own against a continual succession of fresh com- 

 petitors and enemies of all kinds. And even among such 

 Holarctic forms as possess this more or less exceptional 

 adaptability, so that they now extend into districts lying 

 as far south as Notogaea, probably a few only had reached 

 the parts of Asia adjacent to Australia when the latter 

 became inaccessible by its isolation. Had that isolation 

 been a little longer delayed, Australia might probably have 

 received from Arctogaea both Sawflies (e. g. Aihalia and 

 Stromboceros) and Mammals (e. g. T a pints and Elephas) 

 which seem never to have actually reached it. It is also 

 not surprising that the type of Sawfly (" Tenthredo anten- 

 nis filiformibus : articulis 7-9"" of Linne) which is most 

 dominant of all in Holarctic districts — no doubt because it 

 is best adapted to their special surroundings — should be 

 precisely that which is most conspicuously absent from 

 Notogaea, or, at any rate, from Australia. Whereas groups 

 which have a more cosmopolitan range {Arginae, Lophyrinae, 

 and Cimbicinae) though not unrepresented in Arctogaea 

 form comparatively a very small part * of its Fauna. 



I will now enumerate some of the most definite ways in 

 which Australian forms differ often or always from the 

 most normal Arctogaeic Sawflies. Not all the characters 

 to which attention will be called are invariable in Australia 

 or Arctogaea as the case may be ; but some really are so, 

 when we lake them one by one; and others are combined 

 together in one Realm in a way to which we cannot find 

 parallels in the other. Considered as a whole they help 

 to show, what has already been shown often and perhaps 

 more conclusively by other kinds of evidence, (1) that the 

 Fauna of Australia is as distinct as we should expect it to be 

 from its long isolation. (2) that it includes representatives 

 of only a tew oi the groups occurring elsewhere. (3) and 

 that, however the fact is to be explained, there is more 

 appearance of affinity between certain Neogaeic and Noto 



* A rough calculation, based chiefly on localities cited by Konow 

 n, Genera Insectorum, gives us in Arctogaea -1 Arginae only out of 

 nearly loo genera peculiar to it, in Neogaea L6 out of '.i'i, and in 



Notogaea '.I out of !•">. 



