206 SPENCER MOORE [September 



and under its influence the seeds germinate ; hereupon the temperature 

 suddenly falls, and the young .and tender seedlings are exposed, at a 

 critical period in their career, to entirely new and unfavourable con- 

 ditions, and they perish accordingly. It is therefore no matter for 

 wonder, and still less for drawing conclusions as to " aggressive power " 

 and " superiority " of the northern species, if introductions from the 

 northern hemisphere are enabled to exist and multiply in the southern, 

 while an embargo is placed upon southern species in Northern and 

 Central Europe. Moreover, that this is the real reason why southern 

 species are not domiciled with us seems clear when it is remembered 

 how, in northern countries where the conditions are approximately 

 similar to those obtaining in the southern hemisphere, southern intro- 

 ductions are able to maintain themselves. One may cite, for example, 

 the Western Mediterranean seaboard and the coast of Portugal, where 

 a fair number of southern species — most of them, it is true, South 

 African, from greater facility of intercourse — have succeeded in estab- 

 lishing themselves, and apparently at some expense to the indigenous 

 flora. 



There is one country north of the equator where Australian species 

 readily become naturalised. Botanists who hold fast by the theory 

 that the Australian flora is a mere geographical survival have been 

 puzzled — -as assuredly they ought to be puzzled — by the headway 

 that species from Australia make when introduced into Southern 

 India ; nor does Mr. Wallace's solution of the problem, ingenious 

 though it be, at all relieve matters. Mr. Wallace cheerily avers that 

 this fact is quite in harmony with the presumed predominance of 

 northern forms. " For," he says, " not only is the climate favourable, 

 but the entire Indian peninsula has existed for untold ages as an 

 island, and thus possesses the insular characteristics of a compara- 

 tively poor and less developed flora and fauna as compared with the 

 truly continental Malayan and Himalayan regions. Thus Australian 

 plants can compete with a fair chance of success." 1 But what 

 evidence is there for Mr. Wallace's idea ? We venture to maintain, 

 on the contrary, that the Indian flora is, in all essentials, a continental 

 one, and, moreover, the " untold ages " Mr. Wallace alludes to are 

 scarcely in point, for what we want is evidence as to the continued 

 insularity, in a botanical sense, of a region which, for many thousands 

 of years at least, has ceased to be an island. But why travel so far 

 in search of an explanation when one is ready to hand ? Why not 

 admit that Australian species flourish in the Neilgherries simply 

 because the present climate of that district is suitable to them ? And 

 why not go a step further, and allow that if a land connection existed 

 between Australia and South India, and the intervening country 

 enjoyed a climate like that of Australia, a considerable number of 



1 "Island Life," p. 496, note. The fact there cited was communicated to Mr. Wallace 

 by Sir Joseph Hooker. 



