NATURE-STUDY LESSONS. 49 



(c) After observing the way in which the frog 



swallows its food, infer the use of teeth to 

 the frog. 



(d) Compare as to size, number and position, the 



teeth of a frog with those of the cat, snake 

 and fish. 



(3) T/ie Tongue. 



23. {a) Discover where the tongue is attached in the 



mouth. 

 {b) Where does the end lie ? 

 {c) Infer the purpose of this arrangement of the 



tongue. 

 {cT) Infer the use of the sticky fluid covering the 



tongue. 



24. Draw the open mouth of the frog, showing the 

 tongue and the teeth. 



25. If you have seen the frog catching an insect, draw 

 the tongue in the act. 



(4) The Eyes. 



26. (a) Note their position. 



(J)) Gently touch the eye and note the result. 



(c) How many eyelids are there? Where are 



they when not in use? 

 {d) Observe the shape of the pupil 

 {e) Draw an eye. 



(5) The Nostrils. 



27. Discover them and note their number and position. 



(6) The Ears. 



28. {a) Discover whether the frog can hear. 

 (^) Where is the ear-drum placed ? 



