Book News and Reviews 



299 



oTtfii rolihcd us of (i|)p(irtuiiities to solve 

 llu' mystery of llu'ir ri'lalioiisliips, and 

 what littk' \vc do know alxiut thcni. 

 Professor Barrows must admit, wc owe 

 largely to those bird students who luive 

 been armed with opera-glass and camera, 

 rather than with a gun. And it is to the 

 observations of these same students that 

 we must turn for the largest and most 

 important contributions to our knowledge 

 of the life-histories of our birds which 

 have been made in the past fifteen years. 

 This is as it should be, and the fact serves 

 to mark an advance in our methods of 

 study resulting from the increased advan- 

 tages which the l)ir(l student of toda>' 

 possesses. 



Time was in eastern North America 

 when collecting was necessary, but unless 

 the student has some deiinite use for 

 specimens as specimens, he may proceed 

 with his study without killing its object. 

 Keys for identification and elaborate 

 faunal treatises now solve his problems 

 of identification and give him detailed 

 information in regard to times of occur- 

 rence, and among works of this kind 

 none, we are sure, will prove to be more 

 useful than this admirable work b\' 

 I'rt)fessor Barrows. — F. AI. C. 



Distribution and Origin of Life in 

 .\merica. By Robert Francis 

 ScHARFF, Ph.B., B. So. New York. 

 The Macmillan Company, 191 2, 8vo., 

 xvi -|- 497 pages, 21 maps. Price $3. 



Dr. Scharfl has placed in this volume 

 an immense amount of information in 

 regard to the distribution of animals, and 

 while we doubt if his interpretation of the 

 facts presented will find wide acceptance 

 by zoogeographers, his most aggressive 

 critic cannot but be thankful for the data 

 which he has made so easily available 

 for reference. 



Dr. Scharff is a continent builder; he 

 takes the most surprising liberties with 

 the earth's surface, throwing out bridges 

 connecting hemisphere with hemisphere 

 in defiance of geologic probabilities, and 

 where the negative evidence outweighs 

 the positive many times over. 



Negative evidence, however, he is 



inclined to ignore nor does he make due 

 allowance for the often obvious incom- 

 pleteness of recorded information, while 

 an examination of specimens rather than 

 records would readily convince Dr. 

 .ScharfT that he has given undue weight 

 to ditTerences between closely allied forms. 



To read, for e.\amplc, his remarks on 

 Bermuda birds would lead one to believe 

 that most of the barely recognizable 

 forms inhabiting those islands were 

 strikingly different from their continental 

 relatives, while his comments on the 

 Bluebirds inhabiting Bermuda seem so 

 irrelevant that one almost questions their 

 seriousness. 



These islands, by the way, which have 

 been hitherto regarded as of purely 

 oceanic origin. Dr. Scharff believes "to 

 have formed part of a wide belt of land, 

 which extended northward from the West 

 Indies, joining the mainland of North 

 America somewhere near Massachusetts, 

 at a time when most of the existing coast 

 line of the Atlantic States south of Massa- 

 chusetts was submerged." The fact, 

 however, that Bermuda land-birds find 

 their continental representatives in the 

 South Atlantic States is not mentioned. 



The inlluence of past climatic changes, 

 particularly those occasioned by glacial 

 periods, Dr. Scharff considers of small 

 importance, nor does he give much weight 

 to winds, currents, and other agencies 

 which are usually considered to play a 

 part in forming the life of islands. 



No doubt there is adequate ground for 

 some of Dr. Scharff's theories, but many of 

 them rest on so slight a basis, and he 

 argues for such profound changes in the 

 earth's surface on such relatively unim- 

 portant and insufficient grounds, that we 

 fear his methods will tend to bring the 

 science of zoogeography into disrepute 

 among more conservative students. 



Nevertheless, Dr. Scharff has made a 

 contribution to this subject of the highest 

 importance, and one which must be con- 

 sidered by all future workers in this field; 

 but in our opinion it is a volume for the 

 discriminating naturalist and not for 

 the general reader. — F. M. C. 



