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TEXTBOOK OF ZOOLOGY 



pigeon numbers made by John James Audubon, the celebrated early 

 American artist and ornithologist. He estimated a total of nearly 

 five billion birds in the three states of Kentucky, Ohio, and Indiana 

 along the Ohio River in one year's flight. Old-timers still living in 

 eastern Texas report passenger pigeons as still numerous in the 

 1870 's in parts of that State. So abundant were these birds over 

 their original range that when, after a long period of exploitation, 



Fig. 411. — Passenger pigeon, Ectopistes migratorius. This bird was once extremely 

 abundant but is now extinct. (Courtesy of General Biological Supply House.) 



the inevitable happened, and the species disappeared, many and 

 varied were the explanations offered. But there is really no mystery 

 at all. Carloads of birds were shipped direct to the big city markets 

 for weeks during the nesting season. If there is any mystery, it is 

 that the birds persisted as long as they did. 



The deer family, including some of the most magnificent animals in 

 the world — caribou, moose, elk, mule deer, black-tailed deer, and the 

 Virginia deer — has fortunately, with few exceptions, proved to be 



