416 



ZOOLOGY. 



The Columbcu embrace birds somewhat similar but with 

 weaker legs than those of the preceding order. They have 

 straight beak and compressed nails. The pigeons, doves, and 

 the recently extinct dodo are types. The domestic pigeons, of 

 which there are many interesting varieties, are the descendants 



FIG. 217. 



FIG. 217. Great horned-owl (Bubo virginianus) . Adult female. Photographed from 

 life by Dr. R. W. Shufeldt. 



Questions on the figure. What are the habits of owls? Does the 

 figure show any structural adaptations to known habits? How does the 

 standing position of the owl differ from that of other birds of your 

 acquaintance? See also Figs. 218 and 219. 



