-In Peruvia, prope Casapi (Mathews, n. 1689, Herb. Kew.).-Herba, caulis piloso-pubescens, foliorum maj. limbi 0,05 longi 0,03 lati, petioli 0,008 longi.

(To be continued.)

EXOTIC PLANTS ABOUT LONDON IN 1865.

BY HENRY TRIMEN, M.B. LOND., F.L.S.

The year 1865 was remarkable for its high temperature from April to September. The average temperature of April was (roughly speaking) 53° F., being no less than 6.75° F. above the mean of the last fifty years. On the 27th the highest temperature ever registered in the month was noticed, 81.5° F. May, June, and July all showed a mean temperature considerably above the average, and there were some remarkably high readings registered, but the mean temperature of August fell somewhat below the usual average (1·0° F.). The first twenty days of September were excessively hot, the average of that period, 64.5° F., is 10° F. above the mean of fifty years. Scarcely a drop of rain fell during three weeks. On the 8th, 86° F. was registered, a temperature never equalled in September (except on 6th, in 1846); and the mean temperature, 72·1° F., was higher than that of any day since August 12th, 1861. On the 20th, a thermometer hung in the open air facing the south at Southampton showed, at 11 A.M., 119° F. The mean temperature of the month was nearly 64° F., being about 7.5° above the mean of the last fifty years.

The mean temperature of the whole of the six summer months (April to September inclusive) was about 3° F. above the mean of the same six months during fifty years.

This unusual heat could not but influence vegetation to an important extent. It may, therefore, be worth while to put on record the occurrence of numerous exotics about London last year, the luxuriant growth of some which I believe to be possible in this country only in years with an exceptionably high mean summer temperature.

Mitcham, Surrey, has a rich soil in good cultivation, and the neighbourhood has long been known as a garden on a large scale for the growth of officinal plants. On a farm to the north of the Common

there appeared last summer a large number of foreign plants, many of which I collected in two visits I paid the locality with my friend Mr. Naylor, of Edinburgh, who detected the station, and who went several times to the spot, and always succeeded in finding something new.

The origin of these plants is the same ultimately as that of the exotics found at Wandsworth-the sweepings of corn used and stored up at Messrs. Watney's brewery at Thames' side. This refuse is sold to farmers in the neighbourhood as manure for grass lands, but its small fertilizing value must certainly be overbalanced by the evident risk of introducing foreign weeds into the cornfields round. This, however, has not been considered by the Surrey farmers, who pile the

manure" in heaps on the borders of the fields till wanted; and it is on and around these heaps that the exotics sprang up last year in great abundance. Their origin is evident, and is now clearly stated in order that no mistakes may be made in future by botanists who may find these certainly alien plants, which have no claim whatever as yet to a place in our Flora. Should any become naturalized permanently in the district, it is still more important that the history of their introduction should be known.

Appendix B. of Brewer's 'Flora of Surrey' is a list of the exotics collected by Messrs. Irvine, Woods, Britten, and others, on the ground at Wandsworth where the refuse of the distillery was thrown out and corn sifted. A few more species are recorded in the new series of the 'Phytologist,' and in Mr. Irvine's Handbook of British Plants.' These plants were noticed in 1851, and, though at first numerous, few retained their ground many seasons. In 1863, I saw only about twenty species.

6

The origin of the Mitcham and Wandsworth plants being identical, the species are, as might be expected, in the main the same. Nearly half, however, of those enumerated in the following list have not been recorded from Wandsworth. It is probable that the more favourable conditions of soil and situation caused many seeds to germinate at Mitcham which would have perished in the exposed ground at Wandsworth; and it is certain that all the plants attained a greater degree of luxuriance and perfection of growth in the former than the latter place. I have little doubt, however, that the high temperature of last season enabled several species to come to maturity which in ordinary years would have died.

An advantage attending the unchecked growth of these plants is found in the easier determination of their names. In the stunted specimens alone obtainable at Wandsworth this was often difficult, and I have a suspicion that some names in Mr. Irvine's list may refer to allied species given in mine.

I have here recorded no plants of whose nomenclature I am not satisfied. I do not doubt that four times the number were seen, but a few certain facts are preferable to a number of doubtful observations. Had I thought at the time of publishing a list, I would have collected more and better specimens; but, if the coming summer be favourable, no doubt a plentiful crop of novelties will be produced. The species are mostly Mediterranean; there are several from Central Europe, from Istria and the country round Trieste, and a few species are Egyptian or Syrian. There are also two or three cereals of Europe. Some are likely enough to become cornfield weeds in this country, of the class represented by Agrostemma, Silene anglica, the Papavers, and Chrysanthemum segetum, and some have long been known as naturalized plants. Those marked W. are included in the Wandsworth published lists.

Setaria viridis, though an evident introduction at Mitcham, was recorded by Hudson more than a century back as growing copiously at Battersea, and has frequently been observed there since his time. Many exotics do not grow in this country every season, and I believe this is the case with this plant. Last September it was in vast quantity and of large size along the river-bank of Battersea Park, mixed with S. glauca, Brassica Napus, and Königa maritima. Panicum CrusGalli, also mentioned as a Battersea plant by Hudson, was abundant there last year. I have frequently been at the same place at the same time of year, but never met with these grasses, and cannot but suppose their appearance in such plenty due to the exceptional temperature of September, 1865.

Potentilla recta, L. (a form with small petals). In plenty on the railway bank at Mitcham station last June, but perhaps the remains of a garden.

Mimulus moschatus? (the Musk Plant of gardeners.) Among grass by the river Wandle at Mitcham, in a perfectly wild state. September, 1865.

The following plants were collected at the beginning of August by Mr. Thiselton Dyer, during a visit to the site of the International Exhibition of 1862, at South Kensington :

Glaucium luteum, Scop.
Barbarea præcox, R. Br.

Camelina fœtida, Fr.

Malva crispa, L.

Melilotus cœrulea, Lam.

Hyoscyamus albus, L.

Nicotiana rustica, L.

Datura Stramonium, L., and D. Tatula, L.

Veronica Buxbaumii, Ten.

Chenopodium polyspermum, L., var.

cymoso-spicatum, Koch.

Panicum Crus-Galli, L.

P. miliaceum, L.

And at the same place, Mr. Naylor collected the following in Oc

Carduus arvensis, Curt., var. setosus Cirsium setosum, M. Bieb.
Verbascum Lychnitis, L.

Euphorbia platyphylla, Koch.

Mercurialis annua, var. B. ambigua, L.

It is not so easy to trace the origin of these plants, as in the case of those at Mitcham and Wandsworth. They are, however, as incontestably derived from foreign seeds, perhaps brought with packing material.

ABSTRACT OF AN OFFICIAL REPORT ON THE PROGRESS AND CONDITION OF THE ROYAL GARDENS AT KEW, DURING THE YEAR 1865.

BY J. D. HOOKER, M.D., F.R.S.A., ETC. ETC., DIRECTOR.

Royal Gardens, Kew, W., January 1, 1866. The number of visitors to the Royal Gardens during the past year has been 55,934 in excess of that of 1864; the distribution being :on Sundays, 260,040; on week-days, 269, 201; total, 529,241.

In presenting the report for the past year, I have, in the first place, the painful duty of announcing the decease of the Director, Sir W. J.