Oct., i9i3-JVIar., 1914 
Illustrations 
IX 
Page 
Plate XXXVII (colored;. Fig. A. —A pecan leaflet infected with the brown 
leaf-spot fungus (Cercospora fusca, emend, sp.) from pure 
culture. Fig. B .—A pecan leaflet infected with the 
anthracnose fungus ( Glomerella cingulata (Stonem.) S. 
and v. S.) from pure culture. Fig. C. —View of upper 
surface of a pecan leaflet recently infected with the 
nursery-blight fungus ( Phyllosticta caryae Peck) from 
pure culture. Fig. D. —A pecan kernel infected with 
the kernel-spot fungus ( Coniothyrium caryogenum, n. sp.) 
from a pure culture, showing the appearance eight days 
after inoculation. Fig. E .—A pecan kernel with the 
kernel-spot from natural infection. Fig. F .—A pecan 
nut infected with the anthracnose fungus from pure cul¬ 
ture. Fig. G. —The nursery-blight fungus upon syn¬ 
thetic agar after two weeks. Fig. H .—The nursery- 
blight fungus on corn-meal agar after two weeks. Fig. 
I .—Viewsof the upper and lower surfaces of pecan leaflets, 
showing an advanced stage of the nursery-blight. Fig. J .— 
The brown leaf-spot fungus on synthetic agar after four 
weeks. Fig. K .—The brown leafspot fungus on corn- 
meal agar after four weeks. 338 
XXXVIII. An oak ( Quercus gambelii) inoculated with Diplodia longis - 
pora at X when dormant.*. 346 
XXXIX. Injury caused by potato weevils. Fig. 1.—A section of a 
potato from Peru, showing the larva of Rhigopsidius tucu - 
manus in its burrow. Fig. 2.—A section of a potato, 
showing the burro wings of Rhigopsidius tucumanus . 352 
XL. Rhigopsidius tucumanus Heller. Fig. 1.—Dorsal view. Fig. 
2.—Ventral view. 352 
XLI. Figs. 1 and 2.— Premnotrypes solani Pierce. Fig. 1.—Dorsal 
view. Fig. 2.—Ventral view. Fig. 3.— Trypopremnon 
latithorax Pierce. Dorsal view. 352 
XU I (colored). Sketch map showing the distribution and relative 
areas of the different types of vegetation in Tooele Val¬ 
ley, with detail showing depressions covered with salt- 
flat vegetation alternating with ridges bearing greasewood- 
shadscale vegetation. 418 
Xlylll. Fig. 1.—Salt-flat vegetation bordering Great Salt Lake with 
a greasewood-shadscale ridge in the foreground, a pure 
stand of Salicornia utahensis at the right and hummocks 
covered with Allenrolfea occidentals in the background. 
Fig. 2.—Sagebrush association and islands of Kochia 
vegetation in the upper part of Tooele Valley. 418 
XLIV. Sagebrush (Artemisia iridentata). Fig. 1.—A good stand and 
growth, showing the typical appearance of this association 
where the conditions are relatively favorable. Fig. 2.— 
Plants showing the root habit; photographed at the edge 
of a deep “ arroyo ’ * where the soil had recently caved in.. 418 
XLV. Fig. 1.—Sagebrush land which has recently been burned 
over, showing scattered, dead plants of Artemisia triden- 
tata (no living ones), a dense growth of the annual grass 
Bromus tectorum , and scattered plants of Gutierrezia 
sarothrae. Fig. 2.—An advanced stage in succession on 
sagebrush land which has been under cultivation, with 
