8 EXTINCT AND VANISHING MAMMALS 



the mammals they represent, but as a welcome embellishment of 

 the long pages of text. 



The host of correspondents and collaborators, who have contrib- 

 uted first-hand and hitherto unpublished information of very ex- 

 ceptional value, and whose names will be found in proper place 

 on scores of the following pages, deserve the highest gratitude of 

 the sponsors and the compiler of this report. Without their contri- 

 butions the work would have been deprived of one of its most 

 essential features. 



Finally, the most cordial thanks are due to the various authors 

 and publishers whose books and papers have been utilized in the 

 preparation of this work. It is hoped that they will be rewarded in 

 part, at least, by the complete acknowledgment of all items of 

 information so derived. 



Of the following accounts of Old World species, 17, which 

 Dr. Francis Harper did not have opportunity to prepare on account 

 of taking up other investigations, were written by Glover Morrill 

 Allen and are subscribed with his initials. These accounts are in 

 large part based on the data already brought together by Dr. Harper, 

 to whom every credit is due for the extensive research and corres- 

 pondence which he undertook in order to assemble the essential 

 facts. The 17 accounts are: Crocidura juliginosa trichura, Christ- 

 mas Island Shrew; Rattus macleari, Captain Maclear's Rat; Rattus 

 nativitatis, Christmas Island Burrowing Rat; Colobus polykomos 

 and Colobus badius races, Colobus Monkeys; Pan troglodytes and 

 races, the Chimpanzee; Pongo pygmaeus, the Orang-utan; Hippo- 

 potamus amphibius and races, the Hippopotamuses; Choeropsis 

 liberiensis, Pygmy Hippopotamus ; Hyemoschus aquations and races, 

 Water Chevrotains; Cervus elaphus barbarus, North African Red 

 Deer; Loxodonta africana africana, South African Bush Elephant; 

 Diceros bicornis and races, Black Rhino ; Equus burchellii burchellii, 

 Burchell's Zebra; Equus zebra and race, Mountain Zebra; Equus 

 quagga, the Quagga; Oryx gazella and race, Gemsbok; Aegoryx 

 algazel, Scimitar Oryx; and Syncerus caffer caffer, Cape Buffalo. 



G. M. A. 



FACTORS IN THE PROGRESSIVE DEPLETION OF THE 

 OLD WORLD'S MAMMALIAN FAUNAS 



IN the course of the present studies on the mammals that have 

 become extinct during the Christian Era, and on others that are 

 now threatened with the same fate, it has become convincingly 

 evident that the process of extinction is taking place at a steadily 

 accelerated rate. During this period of approximately 2,000 years, 



