214 VERTEBRATES. 



3. The action of the wings. How, in relation to the 

 air, are they moved forward ? Backward ? How are they 

 folded up ? 



4. The use of the tail. Permit the sparrow to fly about 

 a closed room, and observe the rudder-like action of the 

 tail. When the tail is inclined upward, downward, to 

 right or to left, what is the corresponding direction taken 

 in flight ? How is the tail used in effecting a quick 

 stop? 



5. The shape and position of the legs. Note the zigzag 

 position of the three principal joints. Note the position 

 in standing, in perching, and in flight. Placing the feet 

 in the perching position on one finger, note how the toes 

 automatically close and open when the body is lowered 

 toward the finger, or raised away from it. 



6. The action of the legs. Does the sparrow walk ? 

 Slip a wide rubber band over the wings to hold them 

 close, or, what will answer the same purpose, tie their tips 

 together, and note how the bird gets about when using its 

 legs alone. 



7. Respiration. Note what parts of the body visibly 

 expand and contract in breathing. 



8. The eyes. What position do the eyelids assume 

 when wide open; i.e., are there any "corners" to the 

 sparrow's eye ? Thrust a pencil toward the eye, and see 

 the nictitating membrane dart out across the eyeball, and 

 as quickly retreat again. Observe the round, black pupil 

 in the center of the front of the eyeball, and the circular 

 brown iris surrounding it. Take the bird into a dark 

 place, and watch the pupil enlarge. Then bring it quickly 

 out into the strong light again, and see it grow smaller. 



Wet a small piece of cotton with chloroform, and hold 

 it on the nostrils of the bird a moment, until it begins to 

 doze. Then tie the cotton in place, add a few more drops 

 of chloroform, and lay the bird down. In a few moments 



