46 
lies at the apex and that of the lower half close to the dividing wall, 
as appears to be the case in nearly all Leptopuccinias. The pedicel 
is very long, three or four times as long as the spore, and nearly hyaline. 
The spore contents are reddish. 
Among the species of Puccinia occurring upon the Malvaceae (P. 
slierardiana , Kornicke; P. lobcita , B. cff C. $ P. abutili , B. & Br. 5 P. car- 
bonacea , Kalchbr. & Cke.; and P. heterospora , B. & C.) only one, P. 
heterospora , B. & C., resembles P. heterogenea. Both species have this 
in common, that they have one-celled as well as two-celled teleutospores; 
but in other respects they are entirely different. In the two-celled 
spores of P. heterospora (Figs. 4, 5) the septum occupies very different 
positions, while in P. heterogenea it always has its normal position (Figs. 
6 - 0 ). In P. heterospora the two celled spores occur very rarely, while 
in P. heterogenea they are very frequent. The differences come out very 
sharply when the two species are examined mingled together in the 
same preparation. Even macroscopically the two species can be easily 
distinguished from each other. In P. heterospora the single sori are 
small er and darker colored and stand very many together. Finally there 
is a difference in the choice of host plants of the two species. P. hetero¬ 
spora attacks mainly species of Sid a and Abutilon ,* and not Malva. 
With P. heterogenea the opposite is the case. Puccinia heterospora ap¬ 
pears to prefer a tropical or subtropical climate, while P. heterogenea has 
up to this time been found only in regions with a temperate climate. 
On this account it is not impossible that P. heterogenea may occur in 
North America or in Europe. 
The germination of spores takes place very rapidly. Fresh masses 
which had been kept in a moist chamber produced promycelia and 
sporidia from almost all their spores in a few hours. The promycelium 
divides into from four to six cells, the lowest one of which soon loses 
its contents and is incapable of further development (Figs. 14, 15). 
The formation of sporidia takes place in the manner typical of the 
Leptopuccinias. I 11 very moist air the promycelium often falls apart 
into single cells (Figs. 17, 18). The process of germination is quite 
different when the spores are in water. They then germinate exactly 
like uredospores; a long, non-septate germ tube, often bent backward 
and forward, and with a strongly undulating contour, (Figs. 19-21), 
grows out of the germ pore. Occasionally the commencement of 
branching has been observed at the end of the germ tube (Fig. 21). 
Probably the fungus can reproduce itself by these germ tubes, which, 
because they form no sporidia, penetrate directly into the leaf. But 
it is clear that this method of reproduction is of much less impor¬ 
tance than reproduction by sporidia.* At the most, each spore can pro¬ 
duce two germ tubes, and these can only penetrate into the same leaf 
* Compare Seymour, Distribution of Puccinia heterospora (Journal of Mycology, 
Vol. 1 , p. 94). In previous years in Jamaica I found the species on Abutilon indicum 
A. periplocifolium, and Sida ciliaris. 
