342 ZOOLOGY 



EXERCISES 

 I. GRASSHOPPER (Caloptenus femur-rubrum} 



Caloptenus (which may be replaced by any other member of the 

 Acrididae or by a cricket) can be obtained abundantly in the autumn. 



DRAWINGS 



1. Entire animal, left side, wings in place, x 2. 



2. Front view of head, x 4. 



3. Posterior view of antenna and first and third legs of right side 

 drawn, for comparison, one below the other, x 3. 



4. Upper surface of right wings. Draw a vertical line representing 

 the axis of the body, mark the anterior (yl) and posterior (P) ends of 

 the line, and draw the wings one behind the other to the right of this 

 line, x 3. 



5. Lateral view of trunk (left side), with legs and wings removed, 

 x 3. 



6. Mouth-parts, arrange in a column as in No. 4. x 5. 



7. Compound eye (hand lens), x 10. 



QUESTIONS ON EXTERNAL ANATOMY 



1. Is the number of trunk segments constant? (Count segments of 

 three or more individuals.) 



2. Is the number of segments in the leg constant in the correspond- 

 ing legs of three individuals; in all the legs of the same individual? 



3. Describe in not over one hundred words the difference between 

 the oldest and the youngest individual you have, in respect to () size 

 of trunk ; (I) size of wings ; and (c) other characters. 



OBSERVATIONS ox THE LIVING ANIMAL 



1. Note the respiratory movements of the abdomen. Count the 

 number per minute. Does the number vary with the individual V 

 Does it vary with external conditions such as temperature and stimu- 

 lation ? 



2. Holding the grasshopper in the right hand, with the left put the 

 tip of a blade of green grass to the mouth. Note the movements. 



