433 
peridia as they appear to the naked eye; 15, a very giighly magnified 
view of one of them, the cells of which are magnified 125 diameters ; 
16 one of the cells somewhat more highly magnified. They are not 
always regular in construction, although generally of the form given. 
They separate easily from one another by slight friction. 17 represents 
spores* of an orange color, with which the peridia abound, and which 
consist of at least three parts: first, a transparent outward cell, which 
contains an orange-coloring matter, within which may be seen germinal 
matter in the form of dark spots. The spores are magnilied 125 diame- 
ters. 
All standard works on mycology represent Restelia lacerata as the 
only fungus of the order Meidiacei that attacks hawthorn plants; but 
judging from my investigations, it holds a secondary place. So con- 
spicuous are the species of the two genera on them, the one on the 
leaves, the other on the branches and fruit, that the naked eye can dis- 
tinguish the difference. That on the leaves appears of a brown color. 
Owing to the transparency of the cells of the peridia, the brown coloring- 
matter of the protospores being seen through them, while that on the 
fruit and branches appears of a rich orange, owing to the color of 
their protospores. Although of the same order they differ in genus and 
species. : 
It is of much importance to ascertain as far as possible the conditions 
of growth favorable or unfavorable to this order. Its presence on plants 
is highly destructive to them, and has proved one of the most serious 
obstacles to the cultivation of the hawthorn as a hedge-plant in the 
United States. Forty-seven species of Weidium and three of Restelia 
are reported by M. C. Cooke. In relation to the ravages of this order 
of fungi P. H. Foster, proprietor of Babylon nurseries, Babylon, Long 
Island, writes to the Commissioner of Agriculture, on the 1st of August 
last as follows: 
I send you a specimen of a disease which occurs on some American white-ash trees, 
which I imported from Flushing, New York. I have noticed the disease on them during 
the last two seasons. It first makes its appearance early in the season on the leaves, and 
finally attacks the young wood, as may be seen on the specimens enclosed. It is evi- 
dently of fungoid origin. I have many thousands of plants of American white-ash, 
from two to three years old, planted in my nurseries, none of which are affected with 
this disease. I have also some European ash, which appear to be very susceptible to 
it. I wish to obtain aremedy. The loss of so valuable a timber-tree would be too 
great for our country to bear. 
The Department will at an early day commence a series of experi- 
ments, having relation to the best mode of treatment of plants affected 
with this fungoid form of disease. The results of the experiments will 
be published in the monthly reports. 
THE LINEN INDUSTRY IN SILESIA. 
The culture of flax and the manufacture of linen in Silesia are of the 
ereatest value among the industries of that important section of the 
German Empire. The linens of Silesia have long been celebrated for 
their fine and desirable qualities. In bleaching, what is called the ‘ gen- 
tle process,” in contradistinction to the usual chemical process, is inva- 
*Protospores they should be called, because, in fact, they germinate, and on the 
threads thus produced the true spores or fruit are borne. 
4A 
