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advanced in the flesh, decay followed. One-fourth of an inch beyond the line of decay, in the sound part of the peach, no mycelium could be traced. The cells, however-seen at figg. 8, 9, 10 and 11, Lignographs Cc and Ywere noticed scattered through the sound, fleshy tissues; and also the peculiar forms seen at fig. 12, Lignograph Dd, were occasionally met with. Fig. 8 a, Lignograph Cc, represents sporidia, and new filaments of mycelium, just beginning to vegetate. These sporidia are often met with lying in masses in the flesh, as seen in the figure. Fig. 10, Lignograph Y, represents cells of the yeast plant; e, fig. 7, Lignograph Bb, representa a budding and branching filament, emanating from a sporidium.

August 9th, 4 P.M., peeled a number of ripe peaches and placed them in an earthen dish, mashing them to a jelly and adding about one half their bulk of water, and set them aside, at a temperature of about 75° Fah. „Six hours. after, examined them under the microscope. Found the surface portions completely alive with minute, tremulous, vibrating cells, either single or arranged in lines (fig. 13, Lignograph Ee). These belong to the 80-called vibriones. The following morning--16 hours after the mixturd was made–examined again. Found many of the minute bodies (fig. 13) moving actively about—some in curved lines, and others in zig-zag, progressive ones. There was also noticed large oval and spherical cells (vitab ized cell), having a tremulous and vibrating motion (fig. 14, Lignograph Ee). The larger of them could be seen to contain minute cells.

Aug. 11, 8 A.M.-The vitalized cells (fig. 14) have assumed the appear ance seen in fig. 15. They are quite numerous, and appear to be zoospores. A white mould began to appear on the surface. The surface layer was filled with organized cells (fig. 16) and the mycelium, represented at fig. 17, Lignograph Ff. The zoospores perform the office of organizing these cells (fig. 16). At first the cells in the zoospores are spherical. Their progressive movement, and rotary motion on their progressive line as an axis, rolls the spherical cells into cylinders (fig. 16), when they are voided from the posterior end of the cell. This is a process in the multiplication and organization of cells which, so far as I know, has not before been noticed. *

Fig. 18, Lignograph Dd, represents the spores of the peach fungus vegetating in the flesh of the peaeh.

Aug. 20th. Placed a broken, ripe peach, about one-fourth decayed (fresh picked from the tree, on the decayed part of which was growing the

This mode of the organization and multiplication of cells will be more fully described in another paper, “On cell organization in the various processes of the fermentation of organse matter, vegetable and animal."

fangas, fig. 7 a, Lignograph Bb, and all through the decayed tissues ran the mycelium, fig. 76), in a loosely-covered glass jar, with about one-sixth is bulk of water, and set aside, at a temperature of 75° Fah.

I'wenty-four hours after, examined the peach. It was entirely decayed, xd covered, over the whole surface, with a luxuriant growth of the fungus, fig. 7 a, and through the entire flesh ran the mycelium, fig. 76. In the newly decayed portion there were many vegetating sporidia and zoos pores (fig. 19, Lignograph Dd). At a, are seen two sporidia, the filaments from which anostomoze with each other and are thickly budded.

Fig. 20, Lignograph Dd, represents vitalized cells (so-called vibriones), which posses animalcular motion and are very active, moving rapidly in all directions. There are grounds for believing these bodies to be sper matozoid in character. * They occur in great numbers in all fermenting and decaying bodies.

August 21st, 10 A. M., placed some sporidia of the peach fungus (S. persica) in a solution of sugar in a watch-glass, at 75° F. At 3 P. M.-five hours after—they had vegetated as seen in fig. 21 (Lig. Gg). August 22, 6 A. M., twenty hours after, they had vegetated as seen in fig. 22, (Lig. Dd). Wherever two or more sporidia were near each other, germinating filaments had passed from one to the other, joining them all; and the larger filaments, wherever they had come in contact, had united, producing a system of anostomoses, as seen in Fig. 22.

August 23, 8 A. M., forty-six hours after the sporidia of the peach fun. gus were placed in the saccharine solution, they had begun to branch, and presented the appearance seen in fig. 23, (Lig. Hb).

Progress of the disease in Ohio in 1862.—The young leaves of the peach trees were attacked with the peach fungus (sphasaotheca persica) about the 10th of May, soon after the blossoms had fallen. The attack was general throughout the State, killing nearly all the leaves on the older trees, and

younger ones where they were not vigorous and healthy. On the young, thrifty trees the leaves became thickened, curled, twisted, blistered, overgrown, and yellowish. The more vigorous trees were attacked less than the weaker ones. This parasite spread rapidly in and on the leaves till about June 15th, when it began to decline, and the peach trees began to recover and assume a more healthy appearance. On the 25th of June the trees had very much improved; the leaves had a more healthy green and were less curled. By the 21st of July the fertile plants had almost entirely disappeared, except now and then a few on the new leaves, where they were still developed, but in an enfeebled condition. The pear leaves

on the

• In a paper on which I have been for some time engaged, connected with decay, gangrene, fermentation, &c., I shall have more to offer in relation to these interesting little bodies.

were slightly attacked by the same fungus, during the period of the attack on the peach leaves.

The young peach shoots were first attacked about the 15th of Jane. The plants produced by them were mostly sterile.

The fungus was first noticed on the peach fruit when it was about onethird grown, causing a great share of the crop to wilt, decay, and fall. The portion of the peach crop which survived, was again attacked at the period of its ripening, producing rapid decay in much of the mature and maturing fruit.

PROPHYLACTICS,

Among these may be classed sulphur, sulphurous acid, sulphites, sulphuric acid, and sulphates. These bodies are all more or less destructive to mucedinous growths, and have the power of stopping fermentation. Especially is this the case with sulphur, sulphurous acid, the sulphites, and sulphuric acid. The influence of the sulphates is not so marked.

The wine-grower controls the vegetation of his yeast plants (fermentation) by burning a little sulphur or a few matches in the casks. The sugar manufacturer checks mucedinous cellular development in the juice of the cane (preventing the formation of glucose, which would interfere with granulation) by adding a few drops of sulphuric or sulphurous acid, or a small quantity of some soluble sulphite to the freshly expressed juice,

The experiments which I have performed in this department, were commenced late in May, after the young leaves were completely filled with the mycelium of the peach fungus. The results, therefore, could not be as satisfactory as if commenced when the buds were unfolding into leaves. The sporidia are mostly in the circulating juices of the tree, and in their passage become fixed, and vegetate in the tender developing leaf tissues, which afford them a matrix, with abundant nutrient supplies. The preventative should therefore be applied, so as to enter the sap of the tree in its early circulation in spring, as soon as the flower buds begin to open, that they may reach the sporidia before they begin to vegetate. To this end I would suggest the digging away of the sod around the trees, and the application of a compost containing either sulphur, sulphurous acid, sulphites, or sulphuric acid. The refuse gas lime from the purifying vats of gas establishments, either alone or mixed with coal ashes, cinders from foundries, iron furnaces, and blacksmith shops, or the pitch from coal oil refineries boiled down to asphalt and pulverized, furnish cheap and appropriate materials for the purpose, containing the desired bodies for checking mucedinous growths. These should be mixed with good soil (half and half) before being applied. These bodies all contain valuable nourishment for the trees. They will also guard against many depredations from insects. Care should be taken not to use the gas lime too liberally, When all of these materials can not be obtained, any one two or more may be used. There may also be an advantage derived from scattering a little four of sulphur over the leaves in their early development. The virtues of this body probably lie in its gradual oxydation, forming sulphur

ous acid.

ADDENDA.

Since the foregoing was prepared for the press, we have made the following examinations :

March 3d, 1863.-Examined the swelling buds, and the sprouts of last year's growth of peach trees. The outside bark of the twigs is filled with the spores and mycelium of the peach fungus, and the surface of the twigs is marked by numerous patches of a whitish.gray color, and having & crisped appearance. These patches cover from one-fourth to one-half their surface. Wherever these patches extend, the leaf buds are small and appear shrunken, and many of the flower buds have a dark, dead speck in the centre. Fig. 25, (Lig. Y) presents the appearance of the mycelium and fertile threads, running into lines and branches of spores in the patches of fungus, on the surface of the sprouts and twigs of last year's growth.

LOCUSTS.

Cicada Septemdecemn --Seventeen Year LocustRed Eyed Locust. The locusts commenced making their appearance in Fairfield county, Ohio, in 1863, about May 25th. On May 31st, after some slight thunder showers, they began to make their appearance in multitudes; and on June 1st, 2d, and 3d, they multiplied greatly, so that there was scarcely & square foot of ground which did not contain several pupa cases, and holes from which they had escaped from the soil. On the trunk of a single apple tree, attached to the bark, I have counted as high as sixty-three pupa cases, from which the insects had escaped; while the limbs of the tree, and the ground beneath, were covered with them. This was general throughout the forests and orchards, while they were less numerous in oultivated fields. On June 2d and 3d, they began to fly in large numbers from tree to tree.

June 15th.—The forests and orchards are alive with locusts. A single

tree often contains over a hundred of these insects. Dead locusts begin to appear quite abundantly under the trees in the forests.

June 18th. - Locusts appear to be increasing in number, notwithstanding many are dying. The ends of branches and twigs of fruit and forest trees begin to wilt and die quite extensively, from the borings of locusts (locusts depositing their eggs).

June 26th.—Locusts disappearing slowly; many are dying. Fruit and forest trees are considerably injured by them. Weather has been very dry. Last night a drizzling rain commenced, continuing through the night and most of the day. The soil is wet about six inches below the surface. Wheat harvest will commence here about July ?st.

APPLE BLIGHT AND PEACH CURL IN 1863.

APPLE BLIGHT, The blight attacked the apple, pear, and quince trees, in central Ohio, in 1863, on the 31st of May. There had been some three weeks of very warm, dry weather, quite free from dews and night vapors. The soil had become very dry, and the grass had begun to wither. On the 31st of May there were several small, warm showers, with thunder, followed by fogs and night vapor. On the morning of June 1st, the apple leaves began to wilt, and numerous dead patches were noticed on the small twigs and limbs. This was the first perceptible indication of the disease in this region. From this the disease slowly progressed, invading the apple more than the pear and quince trees,

June 18th.- The blight is progressing but slowly. Has done yet but little injury. The whole of the month of May, and to this date in June, the weather has been unusually dry. The grass has quite ceased growing, and is now drying up; and pastures and meadows are deadening.

Fruit trees have made but very little new wood so far. On account of the dry weather the growth has been unusually slow, there being a deficiency of juices, apparently, in the trees. This slow growth and deficiency of sap, appears to be the cause of the slow progress of the disease, the new layer of wood not being soft and juicy enough to enable the apple blight fungus to grow with its usual luxuriance. *

June 26th.—Disease quite at a stand. Has attacked yet bat comparatively few trees. Invasion slight, and has done but little injury. Weather has been very dry up to last night, when a drizzling rain set in, which has wet the soil about six inches deep.

The extended deadening of the ends of the branches and twigs of fruit and forest trees, since June 18th, produecd by locuste depositing their eggs, should not be confounded with the apple blight.

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