8 



Pyrus sp. Crab apple. Britton, Conn. 



Rihes oxyacanthoides Linn. Gooseberry. Britton, Conn.; Lintner, Felt, N. Y.; 



Alwood, Va.; Troop, Ind. 

 Rihes aureum Pursh. Missouri or flowering currant. Lintner, N. Y. 

 Bibes rubrum Linn. Currant. Britton, Conn.; Lintner, Felt, N. Y. 

 Ribes nigrum Linn. Black currant. Alwood, Va. 



Rosas-p. Britton, Conn.; Lintner, N. Y.; Alwood, Va.; Cockerell, N. Mex.; Bur- 

 gess, Ohio; Troop, Ind.; Gould, Md.; Scott, Ga. 

 Rosa Carolina Linn. Koehler, Conn. 

 Rosa lucida Ehrh. Koehler, Conn. 

 Rosa virginiana Mill. Koehler, Conn. 

 Rosa rugosa Thunb. Britton, Koehler, Conn. 

 SalixBTp. Willow. Britton, Conn.; Felt, N. Y.; Sanderson, Del. 

 Salix lucida Muhl. Koehler, Conn. 



' Salix pentandra Linn. Laurel-leaved willow. Lintner, N. Y.; Alwood, Va. 

 Salix vitellina Linn. Koehler, Conn. 



Salix babylonica Linn. Weeping willow. Lintner, N. Y.; Alwood, Va. 

 Salix humilis 'Marsh. Koehler, Conn. 

 Salix incana Schraiik. Koehler, Conn. 

 Soi-bussp. Mountain ash. Felt, N. Y.; Hunter, Kans. 

 Sorbus americana Marsh. American mountain ash. Britton, Koehler, Conn. ; Alwood, 



Va. 

 Sorbus aucuparia Linn. European mountain ash. Britton, Koehler, Conn. 

 Sorbus melanocarpa C. Koch (Aronia nigra Koehne). Black chokeberry. Koehler, 



Conn. 

 Symphoricarpos racemosus Michx. Snowberrj'. Felt, N. Y.; Smith, N. J. 

 Syringa vulgaris Linn. Common lilac. Burgess, Ohio; commissioner of agriculture, 



N. Y.; Troop, Ind.; Alwood, Va. 

 Syringa persica Linn. Persian lilac. Britton, Conn. 

 Tilia sp. Basswood, linden. Britton, Conn.; Lintner, commissioner of agriculture, 



N.Y. 

 Tilia americana Linn. American linden or basswood. Britton, Conn.; Alwood, Va. 

 Toxylon pomiferum Raf. Osage orange. Britton, Conn.; Lintner, Felt, N. Y.; 



Alwood, Va. 

 Ulmuss]). Elm. Lintner, N. Y.; Webster, Ohio; Troop, Ind. 

 Ulmus aviericana Linn. American elm. Britton, Koehler, Conn.; Alwood, Va. 

 TJlmus campestris Smith. English or European elm. Britton, Conn.; Felt, N. Y.; 



Smith, N.J. 



This list might be materially extended by recording those plants 

 upon which the insect has at various times been taken but to which 

 it is not especially injurious. The fears earlier expressed that the 

 scale would eventually seriously infest our native forest growth have 

 not been borne out, and in effect it requires treatment only on fruit 

 trees and on ornamental trees and plants. 



NATURAL ENEMIES. 



The San Jose scale is subject to attack by numerous predaceous 

 and parasitic enemies, which render important service in its control. 

 Practically, however, the combined influence of these several agen- 

 cies is not sufficient to make up for the enormous reproductive 



[Cir. 124] 



