486 ELEMENTARY BIOLOGY 



8. Passeres. Perching birds ; includes about one half of our native birds. 



(Examples. Sparrows and finches, swallows, robins, thrushes, 

 crows, etc.) 



9. Raptores. Predatory birds. (Examples. Eagle, hawk, owl.) 



10. Pici. (Examples. Woodpeckers, sapsuckers.) 



1 1 . Cuckoo family (including kingfishers). 



1 2. Whip-poor-will order (including humming birds). 



Class 5 Mammalia (mammals). Warm-blooded ; hairy exoskeleton ; 

 diaphragm; suckle young. 



1. Monotremata. Egg-laying mammals. (Examples. Duckbill, spiny 



anteater.) (With the exception of these two, all mammals 

 develop the young within the body of the mother.) 



2. Marsupials. Carry their immature young in a special abdominal 



pouch. (Examples. Kangaroos, wombats, opossums.) 

 The rest of the mammals are divided into the following orders : 



3. Edentata (" toothless " mammals). (Examples. Sloths, armadillos, 



hairy anteaters.) 



4. Cetaceans. (Examples. Whales, dolphins, porpoises.) 



5. Sirenia. (Examples. Sea cow, manatee, dugong.) 



6. Ungulata (" hoofed " animals). 



a. Odd-toe. (Examples. Horses, zebras, rhinoceros.) 



b. Even-toe. (Examples. Ox, sheep, antelope, camel, giraffe, deer, 



pig, hippopotamus.) 



c. Proboscidea (elephants). 



7. Rodentia (" gnawers "). The largest order. (Examples. Rabbits 



and hares, squirrels, chipmunks, porcupine, gopher, muskrat, 

 rats, mice.) 



8. Insectivora (" insect-eaters "). (Examples. Moles, shrews, hedge- 



hog.) 



9. Chiroptera (" hand-wings "). (Examples. Bats, vampire.) 



10. Carnivora ("flesh-eaters"). (Examples. Cat family, dog family, 



bears, weasel, seal, walrus, otter, mink, skunk, badger, 

 raccoon, etc.) 



11. Primates ("the first," or leading, order of animals, including 



man). The families contained in this order are given in the 

 list on page 488. 



506. The orders of insects. The insects constitute the most 

 numerous class of animals. The many species show adapta- 

 tions to all sorts of conditions, and from a human point of 

 view furnish us many friends as well as many enemies. 



