16 



BULLETIN 1201, U. S. DEPARTMENT OF AGRICULTURE. 



Table 4.- 



-Comparative results obtained by spraying aphids iviith the alcoholic 

 and benzene extracts derived from various 1 powders. 



Sam- 

 ple 

 No. 



Preparation. 



Esti- 

 mated 

 num- 

 ber of 

 individ- 

 uals. 



Insects tested. 



Num- 

 ber of 

 sets. 



Species. 



6 hours. 



Percentage of aphids dead 

 within— 1 



1 day. 



2 days. 



3 days. 



510 

 510 

 505 

 505 

 504 

 504 

 511 

 511 

 508 

 508 

 509 

 509 

 507 

 507 

 506 

 506 



510 

 505 

 504 

 511 

 508 



519 

 514 

 513 

 520 

 517 



Alcoholic extract+ 

 soap+water (2+4+ 

 100): 



Sabadilla 



Do 



Chinaberry 



Do 



Amianthium 



Do 



Castor bean 



Do 



Hellebore 



Do 



Pyrethrum 



Do 



Derris 



Do 



"Cube" 



Do 



Control, aIeohol+ 

 soap+water(2+ 



4+100) 



Do 



Alcoholic extract+ 

 soap + water (8+ 

 2+100): 



Sabadilla 



Chinaberry 



Amianthium 



Castor bean 



Hellebore 



Control, alcohol + 

 soap + water (4+ 



2+100) 



Benzene extract + 

 soap+water (8+ 

 2+100): 



Sabadilla 



Chinaberry 



Amianthium 



Castor bean 



Hellebore 



Control, benzene+ 

 soap+water (8+ 



2+100) 



40 per cent nicotine 

 sulphate (1/1200)+ 

 soap+water (0. 8+ 

 2+100) 



100 

 100 

 100 

 100 

 100 

 100 

 100 

 100 

 100 

 100 

 100 

 100 

 100 

 100 

 100 

 100 



100 

 100 



500 

 500 

 500 

 500 

 500 



500 

 500 

 500 

 500 

 500 



50D 



Aphis sp. A. 

 Aphis sp. B. 

 Aphis sp. A. 

 Aphis sp. B. 

 Aphis sp. A. 

 Aphis sp. B. 

 Aphis sp. A. 

 Aphis sp. B. 

 Aphis sp. A. 

 Aphis sp. B. 

 Aphis sp . A . 

 Aphis sp. B. 

 Aphis sp. A. 

 Aphis sp. B. 

 Aphis sp. A. 

 Aphis sp. B. 



Aphis sp. A. 

 Aphis sp. B. 



Macrosiphum sp. A 



do 



....do 



....do 



....do 



....do 



....do 



....do 



....do 



....do 



....do 



....do 



....do 



20 

 30 

 30 

 40 

 40 

 60 

 30 

 20 

 30 

 40 

 95 

 95 

 95 

 95 

 95 

 100 



40 



60 



90 



95 



75 



75 



50 



40 



75 



70 



100 



100 



100 



99 



100 



100 



90 



100 



1 Where a test did not continue for 3 days, columns are left blank. 



