( 136 ) 



G. BiUK. — ^The Differentiation of Species on the Galapagos Islands and the Origin of the 



Group. In liiolog. Led. Mar. Biol. Lahorat. WoocVs Hull, 1893, pp. 67 — 78. 

 G. Baur. — New observatious on the Oiigin of the Galapagos Islands. In Amer. Naturalisl, 



1807, ]>|i. 661— G80, 864—896, 

 G. Baur. — Birds of the Galapagos Archipelago: A criticism of Mr. Robert Ridgway's 



paper. In Amm: Naturalist, 1897, pp. 777 — 784. 

 A. Agassiz. — The Galapagos Islands. In litM. Mus. Compar. Zool. v xxiii. pp. 56 — 75 



(1892). 

 A. GuNTHER. — President's Anniver.s;iry Address, In I'roc. Linn. Sue. Lund. Oct. 1898, 



pp. U— 29. 



IV. 



GENERAL REMARKS ABOUT THE FAUXA OF THE GALAPAGOS 



ISLANDS. 



To the zoologist the Galapagos Islands are " classic gronnd." Their natural 

 history was unknown until they were visited by the Beagle. It was here that 

 Darwin made many of the observatious, " the importance of which in their bearing 

 upon the study of natural science has never been eiiualled." * Since Darwin's time) 

 however, large collections have been accumulated, chiefly by Dr. Habel in 1868, 

 by the naturalists of the Albatross in 1888 and 1891, by Messrs. Baur and 

 Adams in ISUI, and now by the expedition under Mr. Harris. This material is per- 

 haps larger than any material ever brought together from any area of similarly small 

 dimensions. Although we must admit that we are still sadly in want of biological 

 observations upon many of the birds, and of all knowledge of the nidification and 

 eggs of the land-birds, we can hardly believe that this vast material is " still too 

 fragmentary to warrant any serious attempt to solve the problems to which Mr. 

 Darwin first called attention." t If such collections are not sufficient to throw light 

 upon these problems, no collections will ever do so; and we cannot see how the 

 discovery of five or six more subspecies of land-birds, or of some more accidental 

 visitors, can alter our present conclusions. If we are not able now to solve some of 

 the prol)lems alluded to, then we are afraid it is not want of material that prevents 

 our coming to satisfactory conclusions ; but we are then either not able to deduct 

 sufficiently from the material at hand, or no accumulation of zoological specimens 

 will ever help to answer our questions. 



As it is, we cannot spare our readers a short discussion on the origin of the 

 Galapageian fauna, and we hope that our conclusions may be found to be acceptable, 

 although we cannot e.xplain everything, and although we do not for a moment 

 think that ours will be the last word upon the subject. 



There are two theories : viz., that of Darwin, Wallace, and most other 

 naturalists, that tlie islands were uplifted from the ocean, and never were in con- 

 nection with the continent of America, or with each other ; and that of Dr. Baur, 

 who said that the islands were once connected with America and with each other, 

 aud were submerged in or after the Eocene period. Both these views must be taken 

 into earnest consideration. The geology of the Galapagos Islands shows that their 

 formation is ijuite different from that of the ojjposite mainland of South America,t 



* Salvin iu Tram. Ziml. Sue. Lvml. \'ol. IX. p. 4iil. 



t Ridgway in Proc. C.S. Xat. Mus. Vol. XIX. p. t59. 



X Agassiz in Bull. Mtis. Conip, Zotyl. Vol, XXIII. pp. 5(5-74. 



