XV. 4 



Oshima: Formosan Termites 



371 



evaporated by exposing the blocks to direct sunlight. Thus, a 

 considerable number of blocks of pine containing different 

 amounts of the oil was prepared. 



The treated blocks were buried in ground infested by Copto- 

 termes formosanus. From time to time they were dug out for 

 inspection, and only the unattacked samples were buried again. 

 This experiment was carried on for nearly two and a half years. 



Table XXVII. — Blocks of Japanese pine treated with solutions of camphor 



green oil. 



[Experiment station, Shakko, near Taihoku. Experiment started August 5, 1914. Blocks 

 inspected March 7, 1915; August 8, 1915; August 28, 1916; and March 24. 1917.] 



1 PER CENT SOLUTION. 



March 7, 1915. 



Inspected. 



Blocks. 



Total. 



N 



Infested 



n 



No 



damage. 



I .rr.ii,-. 



Per cent 

 100 | 



March 7. 1915., . 

 August 8. 1915.. 

 August 28, 1916. 

 March 24. 1917.. 



2 PER CENT SOLUTION. 



62 



65 



7 



7 



1 



6 



6 



2 



4 



6 







6 



3 PER CENT SOLUTION. 



March 7, 1915... 

 August 8. 1915- 

 August 28, 1916. 

 March 24, 1917.. 



March 7, 1915—. 



August 8, 1915- 

 August 28, 1916. 

 March 24. 1917 .. 



67 



51 



16 



16 



9 



7 



7 







7 



7 



• 



7 



5 PER CENT SOLUTION. 



59 



11 



48 



48 



15 



S3 



33 



3 



30 



30 



2 



28 



10 PER CENT SOLUTION. 



March 7, 1915— 

 August 8, 1915.. 

 August 28, 1916. 

 March 24, 1917- 



67 



5 



62 



62 



19 



43 



43 



1 



42 



42 



' 



36 



