1906.] 



PUBLIC DOCUMENT No. 73. 



131 



Experiment II. 



Experiment III. 



Experiment IV. 



Experiment V. 



Experiment VI. 



(a) Ten diseased caterpillars were placed in a jar 

 with 10 normal pupa?. Result: no change 



(6) One diseased caterpillar was put in a jar with 

 10 normal pupa?. Result : 1 normal pupa be- 

 came diseased. 



(c) Ten diseased caterpillars put in a jar with 10 



normal pupas. Result : 2 normal pupa? be- 

 came diseased. 



(d) Five diseased caterpillars put in a jar with 10 



normal pupa?. Result : 1 normal pupa be- 

 came diseased. 



(a) Ten diseased caterpillars were put in ajar with 

 10 normal caterpillars. Result : 9 normal 

 caterpillars became diseased. 



(6) One diseased caterpillar was put in a jar with 

 10 normal caterpillars. Result : 8 normal 

 caterpillars became diseased, 3 of which 

 pupated. 



(c) Ten diseased caterpillars were put in ajar with 



10 normal caterpillars. Result : 3 caterpil- 

 lars became diseased. 



(d) Five diseased caterpillars were put in a jar with 



10 normal caterpillars. Result: no change, 

 (a) Ten diseased pupa? were placed with 10 normal 



caterpillars. 



diseased. 

 (6) Same as (a). 



diseased. 



(c) Same as (a). Result: 6 diseased caterpillars. 



(d) Same as (a). Result: 4 diseased caterpillars. 

 Fifteen diseased pupas were ground to a powder 



and mixed with a tablespoonf ul of water ; 

 pear leaves were washed with this mixture. 



(a) Five normal caterpillars were placed in a jar 

 filled with treated leaves. Result: all be- 

 came diseased. 



(6) Same as (a). Result: 4 caterpillars became 

 diseased. 



(c) Five normal (jypsy caterpillars were treated as 



in (a). Result: 1 became diseased. 



(d) Same as (c). Result: 1 became diseased. 

 Same as Experiment V, only elm leaves were 



used instead of pear, 

 (a) Five normal caterpillars were put in a jar with 



treated leaves. Result : 2 became diseased. 

 (&) Same as (a). Result: 2 became diseased. 



(c) Same as (a), only gypsy caterpillars were used. 



Result : 1 became diseased. 



(d) Same as (c). Result: no change. 



Result : 7 caterpillars became 

 Result : 5 caterpillars became 



