.\,/7i 



Fig. 37.9. Common shrew (Sorex vulgaris). One of the smallest and commonest 

 of mammals. Shrews are quick and ferocious, seldom seen although they may live 

 in a bushy bank in the dooryard. They most nearly represent the ancestors of 

 placental mammals. (After Flower and Lydekker. Courtesy, Rand: The Chordates. 

 Philadelphia, The Blakiston Co., 1950.) 



Fig. 37.10. Long-eared bat (Corynorhinus) pursues a moth. Bats are the only 

 mammals that have attained the power to fly and according to the evidence of 

 fossils they were flying 50 million years ago. In the wings of bats the thumb is 

 always separate from the rest of the wing. When a bat crawls its thumb helps to 

 hook its body along. Note the curled tail-membrane with which some bats capture 

 their prey. (Courtesy, Hamilton: American Mammals. New York, McGraw-Hill 

 Book Co., 1939.) 



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