128 BOTANICAL GAZETTE [FEBRUARY 
it is widely distributed and common. It is in each case, however, 
except possibly in Kansas, closely limited to the particular host on 
which it was reported. 
The parasite attacks all the aerial parts of its host, but, like 
certain species of Synchytrium, it is largely confined to the tissues 
immediately adjoining the vascular bundles. To the naked eye 
each parasite appears as a small bright red spot buried in the tissue 
of the host. When a piece of the infected tissue is examined under 
the microscope, it may be seen that the parasites are of two sorts, 
resting spores and zoosporangia. The resting spores are some- 
what deeply buried in the tissue of the host, but their superficial 
origin may be demonstrated by the persistence of the original germ 
tube with its external button, Cystenhdut (fig. 4), through which 
the parasite penetrated the host. The zoosporangia (fig. 28) are 
irregularly turbinate or retort-shaped bodies with wide flaring 
necks, through which their contents are emptied at maturity as 
biciliate zoospores which spread the infection during the growing 
season. From the basal portions of both sorts of cysts numerous 
rhizoids are given off, which penetrate the vascular bundles of the 
host, especially their phloem elements, and gather nutrient for the 
parasite. 
In carrying out the investigation I have been aided to an unusual 
degree by my friends. I desire to extend my thanks and acknowl- 
edgments to Messrs. F. L. Stevens and J. G. Hatt of the North 
Carolina Experiment Station for the material, especially to the 
latter gentleman, who has put himself to no little inconvenience in 
killing material at all hours of the night as well as in seasons of 
the year when it was difficult to secure; to Professor GEORGE F. 
‘ATKINSON, who himself planned to make detailed studies upon the 
plant, for the generous way in which he encouraged me to proceed 
with the present investigation; and to Professors ROLAND THAXTER 
and W. G. Farrow for the courtesies of their laboratory and for 
much valuable criticism and advice. 
The material was killed at Raleigh in chromacetic acid and 
shipped to Columbus in the killing fluid, after which it was dehy- 
drated and imbedded in paraftine in the usual way. The safranin- 
violet combination proved most satisfactory as a stain. Iron 
