316 ANNALS NEW YORK ACADEMY OF SCIENCES 



SO far as they are known. The North American continent we know 

 existed as sucli tlif(»ii,uli<)iit geological time, although extensively flooded 

 at times by shallow seas, esj>ecially during the Middle Cretaceous. The 

 same is presumably true of South America. 



Like Doctor Gadow, Doctor Schiirff makes a wholly unjustifiable use 

 of negative evidence where it may serve to support his views, lie is a 

 much more reckless bridge-builder, and appears to 1)C' quite unconscious 

 of any diiference in ])r()bability between sucli a bi'idgc as the Alaska- 

 Siberia connection and the various t I'ans-Allantic and 1 lans-Pacific 

 bridges which he invokes. Yet tbc Alaskan bridge is in existence to-day, 

 only a few yards of its planking removcMl, if one may so speak, tlic sub- 

 structure intact, an<l the uuiiks of the missing planks still showing on 

 tlic midamagcd portion, while tlie buge bridges wbieb lie "pi'd'ers"' to 

 believe in are, except for the Icelandic ridge, scarcely indicated by so 

 much as a sandbank on the flat abyssal floor of the vast intervening 

 oceans. I'hat he can claim support of a kind from so liigli an aiilbority 

 as Suess may be true, but scientific- ])roblenis sliould be settled by ex- 

 amination of the evidence, not by (Stations of opinion from selected 

 authorities. -'*■ 



Doctor Scharft' does not at all believe in accidental ti-ansportatioii by 

 floating vegetation or other natural means. Why, he demands, do not 

 the advocates of such views cite instances of such transportation in mod- 

 ern times, and Avhy is it only the more ancient animals that are so trans- 

 ported? The argument is curiously parallel to the favorite anti-evolu- 

 tionist demand. Why, if man has evolved from a monkey, do not the 

 scientists take a monkey and turn him into a man ? Of course, the proof 

 demanded is an impossibility. If any instances of such transportation 

 were noted during the last few centuries, they would be ascribed to 

 human agency; but the probabilities witliin that time ai'c slight e.\ce]tt 

 in islands near the coast, such as Krakataua : foi- more distant islands 

 they are made probable only by the \ast length of geological ]ieriods. and 

 it is a matter of course that the more ancient the type, the longer time 

 and consequently better chance there has been for its transportation ])y 

 accidental agencies. 



Like all authors who advocate union of the (Jalajiagos islands with the 

 mainland. Dr. Scharff does not distinguish between a union of the islands 

 with each other, which is geologically probable and is an almost uiuivoid- 

 able conclusion from a study of the fauna, and their union with the 

 mainland, which is highly improbable on geological and physiographical 

 grounds, and is not merely unnecessary to explain the fauna but im- 

 possible to reconcile with its peculiarities by any reasonable theories 

 which take into account all of the consequences of such union. 



