298 L. R. CLKYM AND. 



and third form young adults and 150 soldiers have been isolated 

 from these colonies and have been used in experiments. And 

 several hundred have been kept for observations. Thousands 

 of workers and first forms have figured in experiments and 

 observations. 



One experiment, which was later duplicated five times with 

 the same result each time, was carried out as follows: Five 

 individuals of each of the five castes, workers, soldiers, third 

 forms, second forms, and first forms, were placed in each of 

 five large size sputum jars with food. These jars were kept in 

 a moist chamber, so that the moisture, as well as temperature 

 and light, would be identical in all the experiments. Experience 

 has also shown that this is the best way to keep a colony of 

 termites normal in the laboratory. Another experiment, which 

 was duplicated three times with the same result each time, was 

 carried out in the same manner as the experiment just mentioned 

 except that the termites were kept in screw-top jars w r hich were 

 not placed in a moist chamber. In both of these experiments 

 the second forms, the third forms, and the soldiers were all dead, 

 in even- instance, within three to four weeks, while the first 

 forms and workers were able to live indefinitely. 



Many observations were made daily throughout the course of 

 these experiments and no castes except the workers and first 

 forms were ever seen to take food. At various intervals several 

 individuals were killed and their intestinal contents were care- 

 fully examined microscopically, with the result that no wood 







particles were ever present except in the workers, first forms, 

 and soldiers just how the soldiers came to have wood particles 

 in their intestines and yet were not able to live will be made 

 clear later. It seems quite evident, indeed, then, that the young 

 second and third form adults do not feed on wood ; that they get 

 their nourishment perhaps in the form of salivary secretions 

 from the xylophagous members of the colony. 



Why do some castes die when placed by themselves? Is it 

 because they do not take food? To test this point further, 

 twenty experiments were carried out, ten where one worker was 

 placed in a vial with two second form individuals and ten where 

 one worker was placed in a vial with t\v<> soldiers. I'nder this 

 condition, the second forms and soldiers were able to live in- 



