194 Distribution of MotJis of the Siib-jainily Bistonince. 



to the little band of which our Lophodes sinistraria is a repre- 

 sentative, and when the problem of .one is solved so is that 

 of the other. Here, however, let lis make ourselves clear — 

 there must be no mistake — whilst our insect is assuredly 

 Palaearctic, there are a few — a very few — forms of temperate 

 habit which have been handed down through the ages from 

 the once fertile Antarctic continent. 



But it might be urged that the very reason given for the 

 rejection of a remote southern origin of our element is precisely 

 the explanation we require ; it may be that such animals and 

 plants passed down the mountain ranges which form the 

 backbone of North and South America and thence across the 

 Pacific by some narrow belt of land in temperate latitudes. 

 Alas, however, this conjecture, whilst falling in beautifully 

 with the nature of the Holarctic element of South America, 

 Australia, and New Zealand which, as we have seen, comprises 

 only Alpine and Subalpine forms, practically demolishes itself. 

 It necessarily demands that such forms should be alike in the 

 two areas or one the derivative of the other, the Australian and 

 New Zealand contingent being the derived one. What do we 

 find ? Behold the common British Alpine and Subalpine 

 grasses found in Patagonia and Tierra del Fuego : — Phleum 

 alpinnm, Deschampia flexnosa and Agropyyum repens. Contrast 

 it with the following list of similar British species represented 

 in Australia and New Zealand : — Alopecurus genicidaius, 

 Hierochloe borealis, Agrostis canina, Deschampia caespilosa, 

 Koeleria cristata and Festitca duriuscula. Not one is common 

 to the two continents. Besides, many widespread genera in 

 other groups are found in the one and are lacking in the other, 

 e.g., the Jepidopterous genera, Argynnis and C alias, occur in 

 Patagonia and Tierra del Fuego alone, whilst the genus Chyso- 

 pkanus, common enough in New Zealand and elsewhere in the 

 globe, fails in the South American area in question. 



Clearly, neither region obtained this feature of its Flora 

 and Fauna from the other, and once more our dictum the 

 elements common to South America, Australia, and New 

 Zealand are of Secondary and early Tertiary age is confirmed. 



We have incidentally elucidated the history of the Holarctic 

 part of the plants and animals of South America without 

 difficulty, but still no light has been thrown on that of our 

 special quest. 



The similarity of certain forms in Australia and South 

 Africa, e.g., the temperate grasses, suggests that it might be 

 profitable to look there for a solution, but such a search fails 

 even more disastrously than the previous one. Not a single 

 grass appears in both areas ; we are driven to look elsewhere. 



{To be continued). 



Naturalist, 



