contrast with that causing the Black Spot. Because superficial in its manner of feeding upon its host this mildew can spread rapidly over the rose leaves and quickly become manifest.

There is another rose mildew (Peronospora sparsa Berk.) which differs in many ways from the one last mentioned. It is deeply seated, in that its fine filaments penetrate through all portions of the leaf and afterwards produce upon the surface a fine growth that has suggested the common name of Downy Mildew for this fungous parasite. This mildew is closely related to the ones upon the grape, the onion, the greenhouse lettuce, and several other of the destructive downy mildews.

As we pass along through the rose house some plants are seen to be nearly defoliated. An inspection of the canes will show that they are covered with small pimples, each one of which abounds in spores. These microscopic spores ooze from the pimples or small rifts in the epidermis of the cane and germinate quickly and spread the trouble. This is the Rose Anthracnose (Gloeosporium rose Hals.) and is not distantly related to several of the worst diseases of other cultivated plants. Thus Gloeosporium fructigemium Berk., is a widespread fungous trouble, causing bitter or ripe rot in apples, grapes, and other fruits. The somewhat fatal anthracnose of the raspberry (Gloeosporium venetum Speg.) is another near relative of the trouble in hand. The rose plant is most likely attacked through its young parts by the spores of the anthracnose falling upon the leaves or succulent canes and, if the latter, it may girdle the stem and thereby kill it. A plant thus infested by the anthracnose may send up new canes from near the base of the stem, which in turn are likely to bear pale sickly foliage and finally to be destroyed by the fungus that in this instance may spread to it directly from the old stem. This is one of the most contagious of the fungous diseases of the rose.

Some of the plants in the rose house have foliage that is badly marked with gray, irregular, often quite small spots. If these spots are looked at closely — and a hand lens will assist greatly they are seen dotted over with minute black specks, the sporebearing organs of Sphaerella rosigena Ell., Fig. 1, b. In order that this trouble may have a common name and to avoid the word spot and any confusion with Black Spot the expression Rose Leaf Blight is proposed.

Before we leave the roses, and in answer to a question that has already been asked, I may say that the peculiar discoloration of

the leaves of La France, Fig. 1, d, which may for the lack of a better term be called "bronzing", is, so far as I know, not of fungous origin but probably due to a structural weakness permitting the skin to become scalded by too great sun exposure. We will now pass into the Carnation houses.

The leading fungous

Fungous Diseases of the Carnation. enemy of the Carnations today is the Carnation Rust (Uromyces Caryophyllinus Schr.) This fungus, while quite new to this country, is an old pest in Europe, and doubtless came to us in imported stock, and within the past five years has spread throughout the country. The rust can be quickly distinguished by the plump gray blisters produced upon the leaves and stems. After the epidermis is broken the rusty brown spores escape in great numbers and the affected spots then resemble those produced by other rust fungi upon grains, grasses, and many other plants. Before the time of spore-formation the fungus has sent its slender threads in all directions through the leaf or stem, and the plant has become badly diseased.

The work of the Carnation Leaf Spot fungus (Septoria Dianthi Desm.) is easily recognized by the light brown patches upon the leaf and stem. While not confined to any portion of the plant, upon the stem it is most frequently found between joints. The lower half of the leaf usually has more spots than the upper half, and frequently a leaf bends abruptly downward near the middle when a large spot has weakened it at that point. Occasionally a leaf may have several bends downward and sidewise, due to as many diseased spots. Over the light brown (sometimes reddish) affected areas, there develop a number of minute black specks, which in an old spot can be readily seen with the naked eye. These specks consist of flask-shaped bodies, the walls of which are formed of the interwoven threads of the fungus, and upon the inside a vast number of long needle-shaped spores are produced. The spores, mingled with a viscid substance, ooze from the small opening through the wall of the flask and afterwards become disseminated in various ways. In some of the fungi previously mentioned, the spores have been described as produced without cover upon the surface of the plant, but in the Carnation Septoria the surface is finally reached by the discharge through an opening. When lying upon the surface they may be moved when dry by currents of air, as motes float in a sunbeam. On the other hand any stream of water never so small can carry them along.

In case of plants under glass where watering is frequent it is likely that the wet method of transportation is most active, especially if the hose is used with considerable force. A strong spray playing upon a healthy plant through one affected with the Leaf Spot would be quite sure to carry along an abundance of the spores and leave them in drops of water in a suitable condition for germination. The prevalence of the disease at the base of the clasping leaves of the carnation may be due to the fact that the water is held there longer than elsewhere.

The Carnation Anthracnose (species not fully determined) is a third fungous trouble frequently met with, and may be characterized by sharp-pointed black hairs arranged in microscopic rosettes upon the surface of stem or leaf. The spores are borne upon the tips of radiating threads intermingled with the black hairs. This fungus is fond of moisture and is most frequently found upon the lower stems and leaves that lie upon the earth or are matted together. A whole branch may be destroyed by the anthracnose that has affected its base and checked the flow of sap.

The Leaf Mould (Heterosporium echinulatum Berk.) is a fourth fungous trouble of the Carnation, which is easily distinguished by its forming circular spots in the foliage varying from a small dot to a ring extending across the whole leaf. At first the spot is of a pale ashy color covered with a dense mould, but changes with age to a dark brown. This change of color is due to the maturing, upon the minute branches of the mould, of many spores. When fully ripe the spores are covered with microscopic prickers. In its worst form a plant, and particularly the younger portion, will be literally covered with the blending circular spots of this fungus.

The last fungous disease of the Carnation to be mentioned before passing on to the violet houses is of bacterial origin. The germs of this disease are exceedingly small, there being no threadlike structure or spores as met with in the fungi previously mentioned. Attention is attracted to the victim by the manifest lack of vigor, and the consequent failure to produce the usual number of blooms. If a leaf of a diseased plant is held up to the light many somewhat transparent dots will be observed, varying from a mere point to specks an eighth of an inch in diameter. These dots are the starting points of the bacteria which, swarming in the cells of a leaf, destroy the ordinary green substance (chlorophyll), and finally the leaf becomes discolored and lifeless.