5. What sense organs has a turtle? Which appears to be most highly developed? How do you know? 6. In what various ways is the turtle protected against enemies? (You should state several.) Are you afraid of a turtle? If so, why? Why does the turtle need more protection than the snake or lizard? 7. Describe the color pattern of the turtle you are studying. Is this arrangement of colors the same for others of the same species? 8. Describe the arrangement of the epidermal plates of the turtle's shell. Are the arrangement, number, and form of plates the same for all turtles of this species? Compare with the plates of other species. What variations do you find? Reptiles: A General Review and Library Exercise 1. Characteristics of reptiles. 2. Orders of reptiles. Characteristics and examples of each order. 3. Poisonous snakes found in the United States. The poison fangs of a rattlesnake. Habits of the rattlesnake. 4. Cures for snake bites, fabled and real. 5. Snake charming. 6. Famous poisonous snakes and their habits. 7. The characteristics and habits of alligators. 8. The characteristics and habits of marine turtles. How they differ from pond turtles. 9. For what is each of the following noted? Where does it live? The terrapins? the horned toad? the Gila monster? the chameleon? the glass snake? 10. Reptiles of former (geological) times compared with those of the present. 11. Care of eggs and young. Swallowing of young by snakes. 12. Food of snakes. Defend the proposition that non-poisonous snakes are beneficial and should not be killed wantonly. 13. Investigate and write an account of the economic value of reptiles. #D. STUDIES OF BIRDS# #Vertebrates specialized for Flight# The Living Pigeon _Materials._ Living pigeons in cages, and, if practicable, other birds such as chickens, canaries, and sparrows. _The Body._ 1. What divisions of the body are present? Compare the relative size of these divisions with that of other vertebrates studied. Can you account for the great increase in bulk of the trunk over the other divisions? How do you account for the longer neck? _Flight._ 2. What is the shape of the body? How is the body made smooth? To what is the shape and smoothness adapted? (Recall the appearance of a plucked pigeon or chicken.) 3. Observe the size of the wings by measuring their width and spread (measured from tip to tip when outspread). Where on the body are they attached? How is this point of attachment advantageous? What is the shape of the upper surface of a wing when spread? of the lower surface? How is this shape advantageous in flight? 4. Where are the largest and strongest feathers? How are they arranged with respect to each other: (a) to prevent air passing through on the down stroke of the wing? (b) to permit folding? 5. What is the shape and width of the tail when outspread? when folded? In what way does the tail assist in flight? _Walking and Perching._