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The change of color in the affected leaf is controlled somewhat by the color of the bloom. In the yellow varieties the foliage often turns to some shade of lemon, while purple is not infrequent in the pink sorts. The bacterial germs most likely enter the leaf through the stomates and, multiplying, spread from there.

This bacterial disease sickens the whole plant, and there is no fungous growth that breaks through the epidermis as in the rust, etc. Many other plants are liable to similar affections, the most widely known being the twig or fire blight of the pear, apple, and quince trees.

Fungous Diseases of the Violet. Passing from the carnation to the violet houses, we observe that health does not prevail. Some plants are stunted, others are yellow, while others still have the foliage blotched and spotted in various ways. It will be best for us to single out certain leaves and note the fungi that prey upon them.

The Violet Leaf Spot (Cercospora Viola Sacc.), Figs 2 and 3, as the common name suggests, causes the foliage to become more or less covered with circular spots. There are several fungi causing the spotting of violet leaves, but the Cercospora can usually be detected by the dark centre of the spot due to the multitude of spore-bearing threads that are brown colored. Black moulds of various kinds often flourish upon the dead tissue of the spot and greatly change its appearance.

Another spotting of the violet leaves is caused by another fungus, namely, Phyllosticta Viola Desm., Figs. 4 and 5, of a quite different type from the one above mentioned. By the naked eye, when carefully inspected the Phyllosticta spots are seen to have no dark central area, but scattered over the whole brown spot are minute dark specks in which the spores are borne. The Cercospora spot has the spores on minute aërial branches, but in the Phyllosticta Spot the spores are formed within flask-like bodies, and ooze out of the open neck when mature. Similar to the Phyllostica are a number of other violet parasites, as Marsonia Viola Sacc. Besides these there are some fungi which cause blotching of the leaf and a general collapse of the whole plant. For example, there is an anthracnose (Gloeosporium) of the violet similar to the one mentioned upon the rose. There is a bacterial trouble also, so that the violets are fully supplied with fungous parasites.

Fungous Diseases of Dracaenas. Some of the cultural varieties of Dracaenas, notably the Cordyline terminalis, have failed to

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