WHITE-PINE BLISTEK RUST. 3 
data, especially toward that appearing in the chapter on control, Table 
V, and the list of Ribes species infected in the different States. Much 
difficulty has been encountered in getting satisfactory translations 
of articles published in the Japanese, Russian, Dutch, Swedish, Nor- 
wegian, and Danish languages. Dr. E. P. Meinecke has very kindly 
translated most of the Scandinavian and Danish articles. Mr. Rush 
P. Marshall and Miss M. W. Taylor, have aided in checking and col- 
lating the extensive data here presented. 
In this bulletin the behavior of Cronartium ribicola is given with 
considerable detail. So far as is now known, it agrees essentially 
with the Uredinales in general in its life history and physiology. 
This is the first species of Cronartium to be very intensively investi- 
gated, and as a representative of this important group of forest-tree 
fungi, a detailed knowledge of its life history must form the basis 
for the institution of new methods of management of white-pine 
forests. 
ORIGIN AND DISTRIBUTION OF CRONARTIUM RIBICOLA. 
Some writers (76, 90) have believed that Cronartium ribicola went 
to Europe from America on Ribes aureum, that host being associated 
with it (but not exclusively) in the earlier discoveries of the disease 
in Europe. Magnus, who was of this opinion at first (90), seems to 
have completely rejected this theory and now believes that the dis- 
ease came from western Siberia and the Swiss Alps, where it is sup- 
posed (26, 39, 40, 93, 1-30, 174) to have been endemic on Pinus cembra. 
In 1842 Klotsch issued in the exsiccatse entitled " Herbarium vivum 
mycologicum, No. 490," a specimen labeled "Uredo ribicola" col- 
lected by Lasch at Driessen. Specimens have not been seen by the 
writer, and there is some uncertainty whether or not this is actually 
the uredinial stage of Cronartium ribicola. Sydow (155) gives it as 
a synonym of C. ribicola, but he is the only author known to the 
writer who does so. 
Cronartium ribicola was first certainly found by Dietrich (27) in 
the Baltic provinces of Russia in 1854. He found it upon Ribes 
nigrum, R. "rubrum" and R. " palmatum" and also upon Pinus 
strobus, although at that time it was not known that the two forms 
were stages of a single fungus. * So far as can be determined from 
scientific literature, it was not again noted until 1861 in Finland (81), 
1865 in East Prussia (76), and 1869, when Eriksson (31) found it in 
Sweden on Ribes nigrum, and Hisinger (54) noted the first outbreak 
on pines in Finland. It had attacked Pinus strobus trees 30 years 
old and killed them. In 1883 Rostrup (115) reported an outbreak 
in Denmark on Pinus strobus trees 20 to 30 years old. It was evi- 
dently then generally spread over that country. Still later, Klebahn 
(62, 63) and Tubeuf (169) record it as generally distributed over 
