LABORATORY WORK, II 343 



How does the grasshopper react to different substances on the end of 

 the grass blade ? 



3. Place the grasshopper under a bell-glass and note and record the 

 position of the legs in successive phases of walking. 



TOPICS FOR FURTHER STUDY 



1. Habitat and food of the grasshopper. 2. Distribution of the 

 species studied. 3. Development (general and external). 4. Allies 

 of the grasshopper: cricket, green locusts, walking-sticks, Mantis, 

 cockroaches, earwigs, dragon-flies, ephemerids, termites, the Neurop- 

 tera, Hemiptera, and Homoptera. 



II. BUTTERFLY 



Any one of various species whose larvae can be obtained alive near 

 the end of September may be employed. The cabbage butterfly 

 (Pieris), the milkweed butterfly (Danais),or the swallow-tail butterfly 

 (Papilio) will meet these conditions. 



DRAWINGS 



1. Imago : Dorsal view, wings expanded, x 1 or 2. 



2. Imago : Left side, wings closed. (The bodies in 1 and 2 are to 

 be drawn parallel to each other.) x 1 or 2. 



3. Imago : Front of head, x 10. 



4. Pupa : Left side. 



5. Full-grown larva : Dorsal view. 



6. Full-grown larva : Left side. 



QUESTIONS ON EXTERNAL ANATOMY 



1. How many segments behind the head in (</) the imago? (5) the 

 larva? (c) the pupa? 



2. What external organs of the imago can be identified in the 



o o 



pupa ? 



3. Which feet of the larva correspond to those of the imago ? 



OBSERVATIONS ON THE LIVING LARVA 



Each student (or group of students) should be provided with a 

 glass vessel covered with netting and containing food leaves for keep- 

 ing the larva during pupation. 



