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There is, however, a puzzling and singular mycelial growth, commonly 
found upon diseased Gladiolus corms, which has been pointed to with good reason 
as the probable cause of the disease. This mycelium is not peculiar to the 
Gladiolus, for the same pest destroys the bulbs of Crocus sativus, the bulbs of 
Narcissus, and attacks Potatos, Asparagus, and other plants. It was described 
long ago by Dr. Montagne, and is known in France under the name of Tacon, and 
in this country as ‘‘ Copper-web” or Rhizoctonia crocorum, D.C. This “ Copper- 
web” is obviously very imperfectly understood, for at present the fruit is unknown: 
in fact the very name of Rhizoctonia (like Rhizomorpha) has almost fallen out of 
use, 
In March of the present year the Rev. H. H. Dombrain furnished me with 
a Gladiolus corm in a very bad state of disease. It presented the usual appearances 
of the Gladiolus disease as just described, and was a mature seed-corm destined to 
bloom this year, and not a young offset. On minutely examining this corm under 
the microscope I found all the cells and starch destroyed, probably from the pre- 
vious presence of some corrosive mycelium, and the whole interior more or less 
filled with the bodies here illustrated. Whether these bodies are in any way 
connected with the threads described under Rhizoctonia there is no evidence to 
show, for in the first instance we get threads without fruit, and in the new instance 
now brought forward, fruit without threads, but both the threads and fruit 
apparently produce the same effect of disease upon the corm. Further investigation 
must clear up this point, but in the meanwhile the bodies detected by me are 
undoubtedly new. 
Attention may here be called to the large and magnificent crystals so 
abundant in Gladiolus corms, and shown in this illustration. Crystals are always 
formed in cells, but here the great crystals are many times larger than the largest 
of the decomposed cells of the corm. This phenomenon can only be explained by 
the probable fact of the crystals aggregating and recrystallising after the cells have 
been destroyed by the corrosive mycelium, 
Different views have been expressed as to the nature of the compound spores 
found this year in Gladiolus corms by me. At first sight they appear to super- 
ficially resemble the resting-spores of a Peronospora, but this view may be at once 
dismissed. They greatly resemble Papulaspora, but I am convinced by several 
characters that they do not belong to this genus, or indeed to any mould, but to 
the order Czeomacei. 
These compound spores bear a strong resemblance to the spores of Theca- 
phora, but I believe they really belong to a new species coming under the genus 
(closely allied to Thecaphora) named Urocystis. This new species I propose 
naming Urocystis Gladioli, and it may be characterised as follows :—Sori (or 
clusters of spores in blisters) obliterated or effused, spores large, compound, con- 
sisting of from three to six inner brown cells, and a larger, indefinite number of 
nearly transparent outer cells, both series of cells being fertile Habitat—On and in 
the corms and scapes of Gladioli. (See Plate I., enlarged 200 diam , and A, B, 
Plate II., enlarged 1000 diam.) 
