STATE HORTICULTURAL SOCIETY. 



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nois, it may be safely said, in which late peas grew, was free from this 

 fungus this year. A representation of the fruit speck (peridia) is given in 

 Fig. 3. The spore cases are four to eight, each having four to eight 

 spores. The leaves and stems have a white appearance, as if coated 

 with thin whitewash. 



Fig. 4. Verbena Mould. 



Fig. 3. Pea Mould. 



Verbena Mould. — All who have attempted to propagate verbenas 

 know how liable they are to be attacked by "mildew." Though so 

 well known to the florist, I do not find mention of this plant in the books 

 upon parasitic fungi, and do not know that it has ever been studied, 

 though it could hardly escape the numerous eyes that have searched for 

 such things. It too is, in its first stage, an Oidium, and is represented 

 in Fig. 4. The spores are one - fourteen - hundredths of an inch by 

 one-eight-hundredths, and are more or less granular or figured within. I 

 have searched diligently for the second form of fruit without success, but 

 as the plants mostly examined have been in-doors after the cold weather, 

 it may be circumstances were not proper for their development. We 

 have, however, a wild verbena (V. hastata) growing abundantly in open 

 woods and pastures, whose leaves were conspicuous for their whitened 

 appearance during the autumn months. This plant grows erect two to 

 six feet high, branched above, bearing long spikes of seed pods and 

 small flowers. The mildew in itsOidium form is very similar if not iden- 

 tical with that upon the cultivated plant, and the globular fruit bodies 

 are very numerous after November ist. This strengthens the opinion 

 that, under favorable conditions the mildew of the garden verbena is 

 really an Erysiphe quite similar to that affecting the pea. The sporangia 

 or spore cases from the wild plant are about four in each globular concep- 

 tacle, and have uniformly eight spores. The arm-like appendages are 

 yellowish in color, and much crooked and twisted. It may be called 

 sometime Erysiphe verbena', if really found to be without a name. 



Lilac Mould. — The common lilac is almost universally afflicted in the 

 latter part of the summer, with a parasite of this class, the leaves appear- 

 ing as if ( overed with whitisii dust from the highway; indeed, few per- 



