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virginiana leaves collected at Ute Pass, Col., and sent me by Prof. Wm. 
Trelease; in some respects it resembles Exoascus deformans, but the 
spores are larger, being 5 x 7". Prunus demissa, the western choke-cherry 
collected in Nebraska by Mr. T. A. Win.ams, and sent me for examina- 
tion by Mr. T. B. Galloway, shows the characteristic leaf and sprout for- 
mation and agrees microscopically with the fungus upon P, virginianaP 
I have since examined a large amount of material that I have collected 
in the Rocky Mountains, and it seems to me that this fungus closely resem- 
bles the form described above and should be so referred and that Atkin- 
son’s^ E. varius on Prunus virginiana should also be referred to this 
species. 
I have found it onl,j" on Prunus demissa in the Rocky Mountains. 
TAPHRINA, Pries. 
History. The genus Taphina was established by Priest The careful 
and exhaustive studies of Sadebeck seem to warrant maintaining this 
genus distinct from Exoascus. The species of TapJirina are characterized 
as follows: They are all parasitic without perennial mycelium; the fun- 
gus is propagated entirely by the infection of spores. The spores germin- 
ate under favorable conditions, gain an entrance into the host and form 
a subcuticular mycelium not entering the tissues of its host. The hyphae 
are differentiated into two parts, one becoming the hymenium, the other 
taking nourishment from its host, with age loses its contents and finally 
disappears. These fungi affect the leaves by forming spots of various 
size, which sometimes may involve the whole lower or upper surface of 
the leaf. :||r| 
The genus Taphrina is widely distributed in this country. A few of 
the species are troublesome to forest trees; Taphrina aurea occurring on 
the leaves of Populus; T. joJiansonii on the satkins of Populus tremu- 
loides and other species; T. virginica on the leaves of Ostrya virginica; 
T. ulmi on elms and T. caerulescens on various species of oaks. The last 
is the only species observed by the writer in the Rocky mountain coun- 
try, but others no doubt will be brought to light. 
Taphrina caerulescens (Mont. & DesM.) Tul. 
History. This fungus was described by Montague and DesMaziere^ 
as Ascomyces caerulescens and was incorrectly named Ascomyes quer- 
cus by Cookef Robinson®, however, correctly refers the South Carolina 
material to T. caerulescens. Dr. Robinson reports the fungus on a large 
number of hosts and these were added to by Mrs. Patterson®. 
1. Bull. Cornell Univ. 73 : 
2. Obs. Myc. 1 : 217. 1815. Syst. Myc. 3 : 520. 
See also the following papers for accounts of the genus. 
Tul. Ann. Sc. Nat. V. 5 ; 121. 125. 1806. 
Johanson studier ofver Svampslagtet Taphrina. Bihang till k. Svenska Vet. 
Akad. Handlingar. 13: No. 4. 
Sadebeck. Untersuch, uber die Pilzgattung Exoaascus &c. Kritische Unters- 
uchungen uber die durch Taphrina Arten &c. Die parasitischen Exoasceen 
Hamburg. 1893 : 43. 
Itobinson. Notes on the genus Taphrina. Anals of Bot. 1 ; 163. 
Patterson. A study of North American Parasitic Exoasceae. Bull. Lab. Nat. 
Hist. la. 3: 89. 
Saccardo Syll. Fung. 8 : 812. 
3. Ann. d. Sci. Nat. 111. 10 : 345. 
4. Ravenel’s Fung. Am. No. 72. 
5. Notes on the geenus Taphrina. Annals of Bot. 1 : 174 : 6 North Am. 
parasitic Exoasceae. 114. 
