44 POPULAR SCIENCE MONTHLY. 



and cacique birds which. " possessed the qualities rarely found to- 

 gether, of melodious song and brilliant plumage. Toucans made 

 the woods resonant with their sharp accents, which were mingled 

 with the disagreeable cries of paroquets of numerous species and 

 of red and yellow aras. . . . The woods resounded with the ca- 

 denced cries of the penelope and the hoecos ; by means of his cry 

 at a fixed hour the kamichi serves the Indians instead of a clock." 



The abundance of mammals is still more extraordinary than 

 that of birds. Livingstone speaks of a band of more than ten 

 thousand euchoris antelopes. Delegorgue says, describing a meet- 

 ing he had with these animals : " The dust flew and formed thick 

 clouds in a hundred directions. Sometimes it rose in whirling 

 columns to the height of one hundred or two hundred feet. . . . 

 Immediately I perceived the innumerable troops of springboks 

 which were raising these clouds. . . . The vision astonished me so 

 that I had to question myself in order to be sure that it was not 

 a vision. There were bands of from three to ten thousand indi- 

 viduals each, crossing one another's course at all points at once." 

 The same traveler speaks also of large herds of gnus and elands ; 

 and he speaks of bands of a thousand or fifteen hundred buffaloes. 



Allen, in his admirable work on the bisons of America, gives 

 some curious details on the importance their herds once had and 

 on their extinction. The 2,500,000 bisons that were killed between 

 1870 and 1875 would represent 50,000,000 in a century. 



The solipedes abound in our epoch. Delegorgue saw bands of 

 four or five hundred quaggas in Africa. Mr. Blanford says that 

 Dr. Aitchison met a troop of one thousand herniones in Afghanis- 

 tan. Brehm estimates, following Youatt, that the number of 

 horses in all Russia is near 20,000,000 head. The rapidity with 

 which horses left loose multiply in America is well known. Wild 

 elephants are destined to be annihilated by man, but they are still 

 numerous in some regions. Speke relates that when he was on 

 the banks of the Nile, he found himself in the midst of a drove of 

 several hundred elephants. Delegorgue estimates the number of 

 elephants which he saw on a space about ten thousand feet in 

 diameter in the Amazulu country at six hundred. 



The rodents have a surprising force of propagation and mul- 

 tiply with the most astonishing rapidity. In 1863 a Mr. Austin 

 took some rabbits to Australia for stocking his hunting grounds. 

 The introduction of them was a disaster. They have so multiplied 

 that thousands and thousands of acres of land have been ravaged, 

 and thousands of men ruined. According to a report made three 

 years ago, there are 20,000,000 rabbits in southern Victoria and 

 northern Queensland. Brehm relates that 1,500,000 of field mice 

 {Arvicola arvalis) were destroyed in fifteen days in the canton of 

 Saverne, and that a factory in Breslau having offered a centime 



