FIANTS — INSECTTCIDAI, PROPERTIES. 7 



the others were brought home. The latter were afterwards ground 

 and some of the powder was sent to the writers by Dr. C. H. Eigen- 

 mann, who was in charge of the expedition to Peru and Ecuador. 



According to a letter from Doctor Allen, "cube" or "barbasco" is 

 a woody shrub whose roots contain a milky sap of a very poisonous 

 character. In Peru the sap is used as a wash for cattle to kill ticks 

 and the roots are unlawfully employed to poison fish in streams. 

 (See pp. 10 to 20.) 



The following results were obtained by using " cube." The powder 

 (No. 501), used as a dust, was efficient against potato-beetle larvae 

 (Table 1) and four species of aphids (Aphis spp. A and B, A. 

 rumicis, and Macrosiphum solanifolii, Table 2), but inefficient 

 against Macrosiphum sp. A; used as a fumigant, it was efficient 

 against Macrosiphum sp. G (Table 3) and the one species of lady- 

 beetle tested; used as an infusion (No. 501c), it was efficient against 

 Aphis rumicis and Macrosiphum solanifolii; used as a decoction (No. 

 501a), it was efficient but slow against Aphis spp. A and B ; and used 

 as a hot-water extract (No. 501b), it was efficient against the same 

 species. Used as a cold-water extract (No. 528, Table 7) with soap, 

 it had practically no effect on Macrosiphum solanifolii, M. sp. C*, 

 and Aphis sp. E. 



The cold alcoholic extract (No. 506) of " cube," used without soap, 

 was efficient against silkworms and Macrosiphum sp. A (Table 5) ; 

 used with soap it was efficient against Aphis spp. A. B, and E 

 (Tables 4, 6, and 7) , Macrosiphum sp. A (Tables 5 to 7) , M. rosae, M. 

 solanifolii, M. sp. G, Aphis spiraecola (Table 6), M. liriodendri, and 

 against potato-beetle larvae and sawfly larva?, but inefficient against 

 webworms and the adults of potato beetles; and used with kerosene 

 emulsion, it was efficient against Macrosiphum solanifolii, M. sp. G, 

 and Aphis spp. G, D, and E (Table 6). The hot-water extract (No. 

 525), used with soap, was efficient against Macrosiphum sp. A } but 

 inefficient against Aphis sp. E (Table 7) . The benzene extract, used 

 with soap, was efficient against Macrosiphum sp. A (Table 5), and M. 

 rosae. The dry resin (No. 526) from the powder, dissolved in 

 alcohol and used with soap, was inefficient against Macrosiphum 

 solanifolii, M. sp. G, Aphis spiraecola, and A. sp. E (Table 7). 

 The filtrate (No. 527), obtained from a cold alcoholic extract which 

 had been concentrated, precipitated in water, and filtered, was prac- 

 tically ineffective against Macrosiphum solanifolii, M. sp. G , and 

 Aphis sp. E (Table 7). 



The powder of " cube," dusted into the hair of three cats badly in- 

 fested with Mallophaga, was efficient, but the cats became sick from 

 licking themselves. 



DERRIS. 



Following are the summarized results, obtained by using a com- 

 mercial powder, consisting of a mixture of Derris elliptica and 

 D. uliginosa. The powder, used as a dust (No. 110, Table 2), was 

 efficient against three species of aphids (Aphis sp. A and B, and 

 Macrosiphonella sanborni), and silkworms (Table 1)_, but killed 

 only about half of the Macrosiphum sp. A tested within 24 hours; 

 used as a decoction (No. 110a, not filtered) and also as a hot- water 

 extract (No. 110b, filtered), it was efficient against Aphis sp. A and 

 B (Table 3), and used as a fumigant (No. 110) it was efficient 



