ment of nerve fibre is that most propitious for the transmission. of impressions; while, in the other, one or more of these conditions, essential to the full appreciation and perception of melody, is wanting. Mind has no part in this, for mind has had no opportunity to receive, in the second case, what mind did in the first. Touch, another media, through which mind receives impressions from the without, is dependant upon (in a great measure) the thinness of the epidermis, or outer skin, which covers in the papillæ, or essential element of touch. If this epidermis be thick and horny, as in the hand of the laborer at manual toil, of necessity the impressions of texture and peculiarities of substances, as received through this media, must be less correct and definite, than those brought to the cognizance of the mind, by the delicately-fingered lady's organism.

Taste and smell are subject to the same laws.

We speak of the expression of countenance as being an index of the mental characteristics of the possessor, and assume that these characteristics are the moulders of that expression. This is true, just in the measure we admit that these peculiarities of mental manifestations are the result, directly, of the peculiar physical organism with which that mind is associated; for feature and expression are the title-pages of our physical beings, and only taus, indirectly, of our mentality; for all the mind's pabulum comes through this physical, and all its evolutions are made manifest again through the same channel, and receives its impress in this transmission. But, independent of this subserviency, mind is broader, deeper, and mightier than can be realized, so long as it wears the fetters of the physical, and has no index whatever as to its real peculiarities in that physical.

As the brain is the headquarters of the vast telegraphic company of impressions, and as each nerve has a peculiar class of impressions to transmit, and as these nerves severally, in pairs (the cranial nerves, I mean), are from different and distinct parts of the brain (thus proving that each portion of that brain has a peculiar office), and as brains are variable in size, shape, and texture, are we not justifiable in concluding, that from this

peculiarity of organism, comes much of that which we term individuality? Can we expect men to be alike in apparent power of intellect, when the windows through which those intellects gather visions of the beauty, grandeur, and extent of the vast creation are so variable in size and character? Can we expect them to draw the same conclusions from things so differently seen? A slight pressure on some portion of a nerve, conveying an impression, would materially affect that impression, either to enhance or diminish it; and how often slight impairments in the regularity of the circulation, which may increase or diminish pressure, on a nerve contiguous to a vessel, occurs. And the flow of blood materially influences the action of the brain, increased in quantity and rapidity to a certain extent, and exhilaration and stimulation of brain action are the results; still further increased, and oppression obtains. Hence it is, that good talkers are men who need the stimulus of an audience to quicken their life-current, in order to the highest brainaction. While good writers need no such stimulus, and when under such excitement have brain-action oppressed, by an overflow of blood to that organ. The sluggish, indolent, man, whose pulse beats slow, and whose breath comes in long drawn gusts, when angered, to-morrow, may become quick in thought, and the volley of invective and sarcasm which flows from him will astonish all. Great danger may make him a miracle of invention, daring, and heroism. And these excitants quicken pulse and breath. There are no two individuals physically alike-face and form give personality to each-and there is almost as much dissimilarity in their anatomical structure. Changes in distribution of nerves and arteries are ever met with in the dissecting-room; the same general type of course is followed, but minutiæ is ever variable. Susceptibility to pain varies vastly in different individuals; and this variance is but an example of the degrees of facility of transmission of impressions, in these parties. Mind is not the controller of this, nor, indeed, is it at all responsible for it, but it is simply dependent on the organism of the neural sys

tem.

Our surroundings, as to temperature, purity of atmosphere,

character of food, and necessities for action, are influences of mental manifestations. Under the debilitating influence of a high temperature, how difficult it is to induce brain or muscular action, such as would be almost involuntary in the lower temperatures, unless these be so severe as to overpower us. Who can think in an atmosphere of carbonic acid gas? and the ill-fed being has no higher aim than the attainment of that which will satiate his ever-knawing hunger.

If there had been no necessity for action-if food, water, and clothing had been supplied to the "genus homo," as to plants, what discoveries, what inventions, what language, would then have been? Verily (I believe), none! And, yet, can we say that mind is amenable to temperature, that it is affected by carbonic acid, that it becomes hungry, and needs clothing? And if it be not amenable to these influences, why make it responsible for all those imperfections which are simply the results of an imperfected physical mechanism. Steam is the same power, whether applied to the engine of perfect construction or to one of improper structure, though the manifestations of that power are vastly different. Mind is, I believe, a constant quantity, a spiritual essence, given to all rational beings, in the same measure; and, as I have tried to prove, in the past pages, influenced, so far as its manifestations are concerned, by its entire dependence on the physical, for all intimations of the created universe; and by these more or less perfect impressions, individualized and limited in capability.

With these views of human life before us, dare we critise our fellow-men, condemning their opinions as false and them as dishonest, for entertaining such views? Shall we speak slightingly of who is inappreciative of music, art, and the beauty of nature and has no conception of the grandeur of the world around him? Dare we make light of the poor, "half-witted" being, whose greatest fault is, that that organism, through which mind is made manifest, is signally imperfect, so that no food, no sunlight, no warmth, comes to the imprisoned spirit there; and it hibernates through the long winter of its confinement here, returning to the God who gave it, an infant, yet to develop into the man

hood of soul-growth, after is liberation from the trammels that now starve it? With this belief, will we not find charity more easily exercised, God's goodness more discernible, and be better content with life and our fellow-men? With education, all our physical being becomes more nearly perfect, and, of necessity, our mental manifestations keep pace with the character of culture we give our physical. Sight, hearing, touch, taste, and smell will be the avenues through which beauty or deformity will be perceived by our immortal part; and as we exercise these in the direction of the beautiful in nature, and in thought, so will our mental manifestations partake of the beautiful and good.

ARTICLE VI.

REPORT ON VEGETABLE PARASITES.

PRESENTED TO THE ILLINOIS STATE MICROSCOPICAL SOCIETY, JAN. 14, 1870.

By N. S. DAVIS, M.D., Chairman Committee.

[Published by Request of the Society.]

Parasites are living organizations that attach themselves to, and derive their nourishment from, some other organic body. In one sense, vegetable parasites are such vegetations as attach to, and derive their nourishment from, other vegetable growths. In another sense, they embrace all parasitic growths of vegetable organization, whether attaching to other bodies of vegetable or of animal nature; and it is in this sense that we will use the term vegetable parasite, in this report.

We may divide the whole into two groups or classes. The first embraces such as are found attached to living vegetables only. The second, such as may spring up on either vegetable or animal matter, whether living or dead, under certain combinations of heat, moisture, and light. The first of these classes may be conveniently divided into two orders, namely: the green parasites, or such as have leaves or organs of respiration,

through which they imbibe a part of their nourishment from the atmosphere; and the brown, which have no leaves or respiratory organs, but derive all their nourishment from the roots of the vegetables to which they are attached. They originate under the surface of the ground and shun the light. The first of these orders are described chiefly under the names of Viscum and Loranthus, while the second are represented by the Orabanche and the Latharie.

The second class are termed Fungi and Entophyta; or, in more familiar language, as mushrooms, mould, mildew, smut, rust, blight, etc. They belong to the class Cryptogamia of Linneus, and are distinguished from some of the other orders of that class, chiefly by their deriving their nourishment solely from the organic matter to which they are attached.

They are very numerous, Berkely having given about 600 genera and 4000 species, to which other investigators have added many more since.

To the unassisted eye, few things appear more dissimilar than the large fungous excressences on forest trees, and the mucedo, or filiment of mould; yet, under the microscope, all the varieties of fungi appear to possess a similar organization. They consist primarily of simple cells or spores, united in the form of lines. These may exist separately in the form of extremely delicate filaments, as the mucor, or common mould, or they may be aggregrated in large masses of considerable density, as in the well-known boleti, on the forest trees. Any detailed account of these primary formations, or attempt at classification, would be more tedious than profitable to this Society. For our present purpose, we may divide the whole of what we have denominated the second class into two groups. The first embraces such as are found growing on vegetable products, either living or dead, and constitute the Fungi proper; the second embraces such as are found attached to animal structures, more especially such as are covered with epithelial cells, like the skin and mucous membranes, these have been termed Entophyta.

Many of those embraced in the first group are of great impor