Page:First course in biology (IA firstcourseinbio00bailrich).pdf/399

 its lower surface; its upper surface. What effects are noticed?

Study the scales on the leg of a bird (Fig. 300). Why is the leg scaly rather than feathered from the ankle downward? Which scales are largest? (Fig. 300.) How do the scales on the front and back differ? What can you say of the scales at the bottom of the foot; at the joints of the toes? Explain. How does the covering of the nails and bill compare in color, texture, hardness and firmness of attachment with the scales of the leg?

, i.e. poorly developed at hatching. Young pigeon, naked, beak too weak for eating.

(well developed at hatching). Feathered, able to run and to pick up food. Precocity is a sign of instinctive life and low intelligence. A baby is not precocious.

Question: Is pigeon or fowl exposed to more dangers in infancy?

Draw an outline of the bird seen from the side. Make drawings of the head and feet more detailed and on a larger scale.

Why does a goose have more feathers suitable for making pillows than a fowl? In what country did the domestic fowl originate? (Encyclopedia.) Why does a cock crow for day? (Consider animal life in jungle.)

Activities of a Bird.—Observe a bird eating. Does it seem to chew or break its food before swallowing? Does it have to lift its head in order to swallow food? To swallow drink? Why is there a difference? After feeding the bird, can you feel the food in the crop, or enlargement of the gullet at the base of the neck? (Fig. 304.)

Feel and look for any move-