348 ZOOLOGY 



1. Study the movement of a single leg and draw three of its phases. 

 The Lithobius is held in the covered plate. 1 



2. Make a diagram exhibiting the coordination of leg movement. 



3. Touch the antenna with a needle. Response ? 



4. Bring a clean glass rod near to an antenna ; then the rod dipped 

 in cologne ; then cleaned and dipped in acetic acid. Record results 

 and conclusions. 



5. Does Lithobius tend to move from or toward the source of 

 light? 



6. Place on a piece of filter paper, one-half wet and one-half dry, 

 and note reaction at edge of wet part. 



TOPICS FOR FURTHER STUDY 



1. Habitat and food of chilopods in general. 2. Distribution of 

 Lithobius. 3. Allies of Lithobius : Scutigera, Scolopendra, Geophilus, 

 Polydesmus, Julus ; their habitats. 



VI. SPIDER (Argwpe and Theridium} 



The large black and yellow garden spider (Argiope) should be 

 obtained in the fall and preserved in alcohol. The house cobweb 

 spider (Theridium) can be obtained alive throughout the year in un- 

 swept corners, especially in cellars. Despite its small size it will 

 serve for the studies on activities. It may be kept in a 4-inch battery 

 jar where it will spin its web. Feed upon flies, plant-lice, and other 

 insects. Other spiders may be substituted for these. 



DRAWINGS (of A rgiope) 



1. Ventral view showing appendages, opening to air sacs, and spin- 

 ning glands, x 5. 



2. Side view (left), x 5. 



3. Front dorsal view of head, showing eyes and jaws (hand lens), 

 x 10. 



OBSERVATIONS ON THE LIVING ANIMAL 



Each student should be provided with the following : (1) a glass 

 rod about 10 cm. long and 2 mm. in diameter, or toothpicks ; (2) a 



lr The movements of the animal may be reduced by adding a little ether, or 

 by holding the body with a forceps. 



