BRIEFER ARTICLES. 
Synchytrium on Geranium Carolinianum.—(With plate IV.)—On 
the fourth of February of last year, some distorted leaves were gath- 
ered from Geranium Carolinianum L. growing in a low place in 
the botanical garden at Baton Rouge, La., and examination showed 
the distortions to be due to a Synchytrium. On the margins of some 
of the lobes, and extending in along the veins, on the lower surface, 
were purple-red swellings. The hypertrophy of the diseased parts was 
in many places so great as to cause a cupping of the upper surface. The 
older swollen portions were brown, and had a sticky feel, and the cen- 
ters of the confluent pustules composing them were depressed, giving 
the appearance of small cups placed side by side (fig. 1). The pustules 
were almost entirely confined to the blades of the leaves. 
On the date mentioned, only one Geranium was found affected with 
Synchytrium but in the same locality, three weeks later, the disease 
had spread to a number of individuals, and the red swellings were 
humerous on both petioles and blades. On leaves recently attacked, 
single red pustules were scattered here and there over the lower sur- 
face, occasionally on the upper, but on those longest subjected to the 
action of the fungus, the pustules had multiplied and become con- 
fluent, giving the appearance observed on the Jeaves first collected. 
A section through one of these pustules, in a direction perpendicular 
to the surface of the leaf, shows an elongated, usually pear-shaped 
cavity (figs. 2 and 3), filled with a coarsely granular, reddish brown 
substance whose particles cohere into a sort of network of varying 
openness of texture. Toward the lower part of the cavity, the granu- 
lar material becomes finer and more compact (fig. 3), and imbedded 
In it is either a sorus or a resting-spore; in the material examined, sori 
were far more numerous than resting-spores. 
The resting-spores have a dark brown, laminated, outer covering, 
and a delicate, colorless, inner coat (figs. 4 and 5), enclosing yellowish 
granular contents, bearing occasional oil globules. These spores vary 
greatly in size, ranging from 35 to 150/ in diameter. The smaller 
ones often lack the surrounding granular deposit that seems always to 
attend the larger resting-spores and sori, and as many as four are fie- 
quently found in the same cavity (fig. 5). The outer coat of the small 
Spores also appears more compact and more close fitting than that of 
the large ones (figs. 5 and 4). The large spores are usually spherical, 
but not infrequently ellipsoidal, and in very rare cases are crescent 
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