5o6 



Journal of Agricultural Research 



Vol. XIX, No. lo 



Table I. — Place and time of collection, host, manner of germination, and color of the 

 aeciospores in m^issfor most of the specimens collected in igiy and igi8 — Continued 



Place of collection. 



Time of 

 collection. 



Host. 



Manner of 

 germination. 



Color of spores in 

 mass. 



Plate 

 No. 



West Falls Church, Va. 



Vienna, Va 



OldForge, N. Y 



Glen,N.H 



Moimtain Lake, Va. . 

 West Falls Church, Va. 



Portland, Me 



Madison, Wis 



Phillips, Me 



Portland, Me 



East Lansing, Mich. . . 



Sebago Lake, Me 



Michigan 



OldForge, N.Y 



Madison, Wis 



OldForge, N.Y 



West Falls Church, Va. 

 Do 



Do 



Glen, N. H 



Mountain Lake, Va.. 

 French Creek, W. Va. 



Portland, Me 



Smugglers Notch, Vt, 



Madrid, Me 



OldForge, N.Y 



Smugglers Notch, Vt. 



Bancroft, Wis 



Julet, N.Y 



French Creek, W. Va, 



OldForge, N.Y 



Madison, Wis 



Portland, Me 



Sebago, Lake, Me 



Smugglers Notch, Vt. 



Sebago Lake, Me 



Rouses Point, N.Y... 



Sebago Lake, Me 



Moimtain Lake, Va . . 

 Boxmd Brook, N.J... 



May 21 



do. 



June 27 

 June 22 

 June II 

 May 21 



June 24 

 June 4 

 July 3 

 June 24 

 June 30 

 June 23 

 June, 

 June 26 

 July 17 

 June 27 

 May 21 

 July 4 



May 21 

 June 22 

 June II 

 Jime 8 

 Jvme 24 

 July II 

 July 3 

 June 27 

 July II 

 July, 

 June 26 

 June 6 

 June 26 

 June 4 

 June 24 

 June 23 

 July II 

 June 23 

 June 29 

 J une 23 

 Jime II 

 June 17, 



1918 



Cultivated raspberry. 



do 



R. canadensis 



Wild blackberry 



R. alleghainensis 



Cultivated black rasp- 

 berry. 



R. canadensis 



Wild blackberry 



do 



R. canadensis 



Wild blackberry 



R. triflorus 



Wild blackberry 



R. canadensis 



Wild blackberry 



R. canadensis 



Wild black raspberry 



Cultivated black rasp- 

 berry. 



do 



R. canadensis 



R. alleghaniensis 



Black raspberry 



R. canadensis 



R. strigosus 



Wild blackberry 



R. canadensis 



do. 



Glen, N. H Jime 22, 1916 



R. hispidus 



R. canadensis 



Black raspberry. . . 



R. canadensis 



Wild blackberry. . 



R. triflorus 



do 



R. canadensis 



R. triflorus 



Black raspberry. . . 

 Wild blackberry . . 

 R. alleghaniensis . . . 

 Black raspberry. . . 



R. canadensis 



Germ tubes. 



do 



do 



do 



do 



do 



.do 



.do 



.do 



.do 



.do 



.do 



.do 



.do 



.do 



.do 



.do 



.do 



.....do 



do 



do 



do 



do 



do 



do 



do 



do 



do 



do 



do 



do 



do 



do 



do 



do 



do 



do 



do 



do 



No germina- 

 tion. 

 Germ tubes . 



Xanthine yellow 



do 



do 



do 



do 



do 



.do. 

 .do. 

 .do. 

 .do. 

 .do. 

 .do. 

 ."do. 

 .do. 

 .do. 

 .do. 

 .do. 

 .do. 



...do 



...do 



...do 



...do 



...do 



...do 



...do 



...do 



...do 



...do 



...do 



...do 



...do 



...do 



...do 



...do 



...do 



...do 



...do 



...do 



...do 



. . .do 



Color faded. 



94) fig' 

 94. fig 

 94. fig 

 94) fig 

 94) fig 

 94) fig 



94) fig 

 94. fig' 

 94. fig 

 94. fig 

 94) fig 

 94) fig' 

 94. fig 

 94) fig' 

 94. fig 

 94) fig 

 94) fig' 

 94) fig' 



94) fig' 

 94) fig' 

 94. fig' 

 94) fig 

 94. fig' 

 94. fig 

 94. fig 

 94. fig 

 94. fig 

 94. fig 

 94) fig 

 94, fig 

 94) fig 

 94) fig 

 94) fig 

 94) fig 

 94) fig 

 94, fig. 

 94. fig' 

 94. fig 

 94. fig 

 94. fig 



94. fig- 44 



Plate 93 shows spores from 65 different specimens of the short-cycled 

 orange-rust. Figures i to 44 on Plate 94 show spores from 44 different 

 specimens of the long-cycled rust. The figures on these plates demon- 

 strate that, on the whole, the aeciospores of the two rusts are mor- 

 phologically different. The spores of the short-cycled rust are smaller 

 than those of the long-cycled. They are also more angular and more 

 elongated. Their shape is more irregular. It will be seen that the 

 size and shape of the aeciospores from different specimens of the two 

 rusts vary considerably. On this account it is not always possible by 

 observing spores under the microscope to determine with certainty to 

 which group a given specimen may belong. On the other hand, spore 

 characters do make possible a rather accurate separation of specimens 

 belonging to the two rusts. It is difficult to say just how accurate such 

 determinations will be. Much depends on the specimens at hand and 

 on the judgment of the one who undertakes such a task. The writer's 

 determinations by this means have proved to be correct in about 85 



