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with the bark. The root appears to force its way, taking entire possession of the bough by expansion behind the growing-point, and gradually forming an excrescence above the bark somewhat resembling the crown of a root.

The absorption of the juices by the Mistletoe in time causes the decay of that part of the branch cut off from communication with the trunk by it. This I think will account for large plants of Mistletoe, found on the branches, being almost invariably at the end of the branch.

The expansion is a strange phenomenon. The accompanying sketches will convey some idea of the general appearance of different species. They are reduced from nature, the shaded part representing the Mistletoe. (See figs. 4, 5, 6.) A horizontal section of the expansion itself shows concentric rings and medullary rays, but distorted in every possible way, owing, I suppose, to the pressure of the wood of the bough.

A theory has, I think, been started that it may be propagated by fibres running from one plant, and so take possession of the whole tree. I have tried several specimens where on the same bough I obtained two large plants within six inches of each other. But I have failed, as yet, to detect in sections cut from between the two plants, any fibrous connection.

The capricious habit of the plant is very remarkable. In a wide district abounding in White and Lombard poplars there is scarcely a White poplar that is not covered with masses of Mistletoe, while on not a single Lombard can I find even a sprig. On one Ash, standing in a clump of ash-trees, I found ten plants; but not one of the surrounding trees bore a single plant. The same caprice applies to its growth on the Lime and White Thorn, as far as I have been able to ascertain.

The inquiry into the growth of the Mistletoe, a plant enveloped in so much mystery, mythical and natural, is fraught with interest; and I shall be extremely glad if this letter should prove to be the means of exciting or assisting the researches of others.

If one might be allowed to form an opinion from the way in which people generally speak of nettles, the conclusion would be inevitable that they are not only the most useless weeds in creation, but the greatest pests wherewith the earth has been cursed. There are some morose beings in the world who are for ever looking on the dark side, no matter what it is that has its evils, to them it is all evil. For our own part we don't believe in such a doctrine. Our creed is that there is something good in everything, and we have faith in this creed, even though our own knowledge may be too limited to discover all the good which we believe to exist. Stinging nettles are very disagreeable things we confess, either to handle or sit upon, but that they do not deserve wholesome condemnation shall be evident before we have done.

Our indigenous nettles are small and insignificant beside those of tropical countries. It is true that they are by no means scarce, and if there is any luxury in coming into contact with them, it need not remain long unsatisfied. We possess three, some say four, species; the Small Nettle (Urtica urens), and the Great Nettle (Urtica dioica), both of which bear fruit in spikes, and the Roman Nettle (Urtica pilulifera), in which the clusters of fruit are globose. The last is only local, whilst both the former are common everywhere. It is doubtful whether we have any other indigenous plants so often abused, ill-spoken of, or maltreated as nettles. Scarcely any one, from the infant to the grey-beard, speaks a word in their praise, and for insect and fungal parasites they are almost without parallel. Indeed the wonder seems to be that we have nettles at all, since so many enemies combine against them. Yet nettles and parasites increase and multiply and replenish the earth.

There is a nettle found in the East Indies, known to botanists as Urtica crenulata, the handling of which is certainly, "no joke," if the account given by Leschenault de la Tour is a plain, unvarnished tale. He says, "One of the leaves slightly touched the first three fingers of my left hand; at the time I only perceived a slight pricking, to which I paid no attention. This was at seven in the morning. The pain continued to increase; in an hour it had become intolerable; it seemed as if some one was rubbing my fingers with a hot iron. Nevertheless there was no remarkable appearance: neither swelling, nor pustule, nor inflammation. The pain rapidly spread along the arm, as far as the armpit. I was then seized with frequent sneezing, and with a copious running at the nose, as if I had caught a violent cold in the head. About noon I experienced a painful contraction of the back of the jaws, which made me fear an attack of tetanus. I then went to bed, hoping that repose would alleviate my suffering; but it did not abate; on the contrary, it continued nearly the whole of the following night; but I lost the contraction of the jaws about seven in the evening. The next morning the pain began to leave me, and I fell asleep. I continued to suffer for two days; and the pain returned in full force when I put my hand into water. I did not finally lose it for nine days." A similar occurrence took place at the Calcutta Botanic Gardens, and the man who was stung described the sensation, when water was applied to the part, as if boiling oil was being poured over him. The common nettle of the Neilgherry Mountains (fig. 1) and some parts of Northern India (Urtica heterophylla), Roxburgh stated was the most ferocious plant he had ever seen, and that