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a decoction of strawberrj^ leaves than in any other of half-a-dozen 

 fluids used, and begun to develop in about six hours from the 

 time of sowing. The general result of the artificial cultures in 

 the autumn was the production of a mycelium bearing certain 

 spherical sac-like bodies of highly organized structure. The win- 

 ter sowings produced mycelium and outgrowths of an entirely 

 different character, and failed to develop the sac-like bodies of the 

 autumn cultures. Both of these are subjects which Miss Snow 

 hopes to further investigate, and no conclusions concerning them 

 will now be pulilished. 



The sowings of conidia in the spring, obtained from the basidia 

 on the old leaves, produced for the first time mycelium and conidia, 

 like those from which they were derived ; but none of the growths 

 obtained in the autumn or winter appeared on the mycelium 

 grown in the spring. 



Numerous infections were made in April and May, by placing 

 both germinated and ungerminated conidia on the upper and the 

 under surface of young strawberry leaves, which we believed to 

 be previously uncontaminated by the fungus. It was found that 

 the germ-tubes bored their way between epidermal cells of the 

 upper surface, but they were not observed to enter by the storaates 

 of the under surface, although infections took place readily from 

 that surface. Entrance by the stomates was certainly not the 

 usual mode of attack. In about ten days spots, brownish instead 

 of red, appeared on the leaf, and in fourteen days all the places 

 infected usually showed well-defined spots from which conidia 

 were growing. In some cases one leaflet only, in other cases two 

 were infected, and the disease always appeared only on the leaf- 

 lets and in the places infected ; excepting in a few cases where 

 from our control plants, or by other tests we ascertained our 

 plants to be already contaminated. 



The perithecia were diligently sought for, as it was evident that 

 any proof to be obtained in the spring, of their connection with 

 the conidal stage must lie in the artificial cultures of the asco- 

 spores. They were found with mature asci in April ; and on 

 placing an ascus in a hanging-drop, the spores were observed to 

 germinate in about six hours, within the ascus. The germ-tube 

 developed from one end of the spore, passing, in case of four of 

 the spores, to one end of the ascus, perforating it, while the germ- 

 tubes from the remaining four perforated the opposite end, (Fig. 

 8). The mycelium formed by these germ-tubes, was larger than 

 that from the conidia, grew more vigorously, soon producing at 



