CHAP. XIX THE MADAGASCAR GROUP 424 



become partially or wholly submerged before they reached 

 those countries ; otherwise we should find in Madagascar 

 many other animals besides Lemurs, Insectivora, and 

 Viverridse, especially such active arboreal creatures as 

 monkeys and squirrels, such hardy grazers as deer or an- 

 telopes, or such wide-ranging carnivores as foxes or bears. 

 This obliges us to date the disappearance of the hypotheti- 

 cal continent about the earlier part of the Miocene epoch 

 at latest, for during the latter part of that period we know 

 that such animals existed in abundance in every part of 

 the great northern continents wherever we have found 

 organic remains. But the Oriental birds in Madagascar, 

 by whose presence Dr. Hartlaub upholds the theory of a 

 Lemuria, are slightly modified forms of existing Indian 

 genera, or sometimes, as Dr. Hartlaub himself points out, 

 species hardly distinguishable from those of India, Now all 

 the evidence at our command leads us to conclude that, 

 even if these genera and species were in existence in the 

 early Miocene period, they must have had a widely differ- 

 ent distribution from what they have now. Along with so 

 many African and Indian genera of mammals they then 

 probably inhabited Europe, which at that epoch enjoyed a 

 sub-tropical climate ; and this is rendered almost certain 

 by the discovery in the Miocene of France of fossil remains 

 of trogons and jungle-fowl. If, then, these Indian birds 

 date back to the very period during which alone Lemuria 

 could have existed, that continent was quite unnecessary 

 for their introduction into Madagascar, as they could have 

 followed the same track as the mammalia of Miocene 

 Europe and Asia ; while if, as I maintain, they are of more 

 recent date, then Lemuria had ceased to exist, and could 

 not have been the means of their introduction. 



Sicbmerged Islands let ween Madagascar and India. — 

 Looking at the accompanying map of the Indian Ocean, 

 we see that between Madagascar and India there are now 

 extensive shoals and coral reefs, such as are usually held 

 to indicate subsidence ; and we may therefore fairly 

 postulate the former existence here of several large islands, 

 some of them not much inferior to Madagascar itself. 

 These reefs are all separated from each other by very deep 



