rocks of the south of Scotland (Quart. Jour. Geol. Soc., Lond., vii. 149), that the limestone of St Aldeans, Ayrshire, is generally thick bedded or amorphous; it is highly altered, and its chief mass very dark coloured, with white veins, and soapy serpentinous saalbands. This limestone has been contorted and wrenched from its strike. It nevertheless contains many individuals of the Maclurea, some Murchisoniæ, and a Cytheropsis. We thus learn, from the details of sixty-four cases where organic remains have been found in altered rocks, that metamorphism has dealt with them more favourably than hitherto supposed, and it has been rendered probable that there are many cases of animal life, left by a diminished modifying energy, to reward a diligent search. We learn, too, that the great divisions of the paleozoic series, as well as the smaller mineralogical subdivisions, receive from this complex force a treatment differing somewhat both in kind and intensity, but always in accordance with the principles laid down by our great investigators.

The study of metamorphism is of high importance, for it is of very extensive application. It gives us the key to the history and relations of districts which are hopelessly unintelligible to the common inquirer. The want of this key has deprived more than one eminent geologist of the pleasure of announcing splendid discoveries-discoveries which remain to reward hopeful and diligent search.

Some Account of Plants collected in the Counties of Leeds and Grenville, Upper Canada, in July 1862. By GEORGE LAWSON, LL.D., Professor of Chemistry and Natural History, Queen's College of Canada.*

Having accepted a kind invitation from an eminent Canadian judge to join him on one of his circuits, I arrived at Brockville, a comfortable county town on the north bank of the St Lawrence River, at the foot of the Thousand Islands, on Monday, 30th June. We started early on the following morning (1st July), drove rapidly, and soon reached Farmersville, a village in rear of Brockville, and distant from it about * Read before the Botanical Society of Edinburgh, February 12th, 1863.

15 miles. The only unusual plant observed on the way was Echium vulgare, a native of Europe, long known in Virginia as a troublesome weed, and now making its way in Canada. One remarkable instance was mentioned to me of its introduction by a farmer, and its subsequent spread for miles along an adjoining road. The woods passed through presented no unusual features. Throughout Central Canada we have the same constant succession of beech and maple in good lands, with occasional overtopping basswood and elm trees, or widely spreading butternuts; and pines, white cedars, and hickories spread their roots over thinly covered rocks, whilst Larix americana forms a close and impenetrable thicket growth in the swamps, constituting those "tamarack swamps" that are the terror of Canadian travellers. At Farmersville, in addition to the ordinary forest trees, there were fine groves of Carpinus americana (Michx.), a small tree with fluted stem, ash-coloured bark, and hard, tough timber, like ironwood. As an undergrowth, there was an abundance of Zanthoxylum americanum, and several species of Ribes. Viola canadensis was still beautifully in flower, and with it Stellaria longifolia, Oxalis stricta, an upright form with perennial roots, Geum album, Osmorhiza brevistylis, Cryptotenia canadensis, Tiarella cordifolia, Mitella diphylla, Circæa alpina, the last clustering in patches around old stumps. Scattered through the woods there was a profusion of Cornus canadensis, a humble species nearly as small as C. suecica, and differing from it in the larger, broader leaves clustered almost into a verticil at the top of the short stem. In swampy and springy spots, there were fine beds of Naumburgia thyrsiflora, with Chrysosplenium americanum, Carex intumescens, C. gracillima, with the scales of the fertile spikelets hardly awned, C. laxiflora, normal form, C. stellulata, C. scoparia, C. polytrichoides, C. teretiuscula, and various other Cyperaceae and Junci. Lemna minor mantled the pools, and Linnæa borealis garlanded the black old stumps that rose out of sphagnous swamps. In such humid places, Bryum Wahlbergii formed broad patches. Hypnum nitens was found, and Bryum argenteum was everywhere abundant on dry, rocky, and earthy spots. Climacium dendroides was also collected; it is a

common moss in Canada, more so than C. americanum. I have gathered it in almost every locality in Canada that I have hitherto visited, and a moss so prevalent on the north banks of the St Lawrence and Lake Ontario is likely not to be rare in New York State, yet the American botanists do not seem to be well acquainted with it. A rocky shaded bank furnished many other cryptogamic plants, and the ferns were especially fine; large tufts of Aspidium Goldianum, with its beautiful broad, regularly divided fronds, some three or four feet long. Cystopteris fragilis displayed itself in several forms. A few tufts of the slender green thread-like stems of Equisetum scirpoides were met with, and miniature forests of the more stately E. sylvaticum; and there was an abundance of Polypodium vulgare, Lastrea spinulosa, var., Osmunda regalis, var. spectabilis, Lastrea marginalis, Adiantum pedatum, and Polystichum acrostichoides. Neckera pennata is common, and frequently fertile, on the trunks of white cedar (Thuja occidentalis), at the edges of rocky swamps, and on beech and maple in drier woods. Dr T. F. Chamberlain collected for me, not far from Farmersville, fine tufts of Barbula ruralis and Selaginella rupestris.

In the afternoon (1st July), we proceeded to Delta, passing on the way some very large and fine butternut trees (Juglans cinerea). Delta is a village with water-power mills, an hotel, and a few stores; it is picturesquely, but rather uncomfortably situate on the banks of a short stream that connects Upper and Lower Beverley Lakes, and which occasionally overflows its banks when from any cause a sudden rise takes place in the upper lake. The afternoon was spent in examining the locality. The village street itself afforded a number of those plants which accompany the settler and spring up around his dwelling, and which Mr Watson has well named "colonists," to distinguish them from aboriginal plants. The prevalent species in Delta were Leonurus Cardiaca, Nepeta Cataria, Cynoglossum officinale, Galeopsis Tetrahit, Cannabis sativa, and Datura Stramonium. The last, from its almost constant occurrence in our village streets, gardens, and court-yards, is a frequent cause of poisoning. Cases have been lately referred to in the newspapers, and several medical men have

spoken to me of others that occurred in their private practice. In early summer time, the leaves of the Datura are mistaken for "lambs' quarters," that is Chenopodium album, which is in common use as a kind of spinage, and later in the season the green fruit of the Datura attracts the attention of children, who are tempted to eat it in consequence of its resemblance to some kinds of cucumbers, &c. In the summer of 1861, I believe Daturas were exposed for sale in the Quebec marketplace as "pickling cucumbers;" and the same summer, persons brought to me the prickly fruit of a cucurbit, Echinocystis lobata (Torr. and Gr.), and the fruit of Datura Stramonium, which had both grown together in their gardens, to ask which was the right kind to pickle. I need hardly add that a more dangerous mistake could not be made.

There being accumulations of vegetable soil in the Delta valley, overlying, in some parts, a fine blue clay, used extensively for bricks, the indigenous vegetation was luxuriant. Basswood trees (Tilia americana) were in flower; Populus grandidentata grew beside the stream; Fraxinus pubescens, Prunus americana, and P. virginiana, attracted attention; but the original forest had been pretty well cleared, and instead of timber trees there was an abundant and luxuriant undergrowth of shrubs, many of them covered with flowers. Among the more conspicuous were Viburnum acerifolium; Cornus paniculata, various forms, some in flower, some in fruit; Celastrus scandens, with its mellow-toned foliage, sparing flowers, and flexile woody stems, twisted into all conceivable contortions among the branches to which it clung for support, and intermixed, as it often is, with the poison ivy and the more abundant Ampelopsis quinquefolia, whose foliage acquires such bright tints in autumn. There were likewise along the river edge dense tangled thickets of Corylus rostrata, whose large closed involucre envelopes the fruit, and projects beyond its apex in the form of a long beak; this involucre is densely clothed with silky bristles, like cowitch hairs, which are curved at one end, and, being easily detached, pierce the skin of the fingers. Although C. americana is prevalent on the plains west of Canada, and, perhaps, also in the extreme western part of our province, and is likewise the

common species apparently in the United States, yet the common nut of Central Canada is certainly C. rostrata, which, like its classical congener of Europe, usually grows on thinly covered rocks overlooking lakes and streams.

On sloping banks there were acres of Rubus odoratus, covered with its masses of large purple blossoms, each rocky knoll in the background crested with little clumps of the staghorn sumach (Rhus typhina), its long pinnate fern-like leaves overtopped by purple plumes of flowers. Wild vines (Vitis cordifolia) hung in leafy wreaths from the branches of the trees, or were thrown in luxuriant festoons over masses of crumbling rock. Apocynum androsæmifolium showed itself from beneath the higher bushes, and formed a low hedge-like edging along the side of the path over which its slender stalks bent beneath its neat, trim foliage, and clusters of maidenblush flowers. Of other herbaceous plants observed were Ranunculus recurvatus, Desmodium canadense, a fine plant, Epilobium coloratum, Geum album, Osmorhiza brevistylis, Cryptotania canadensis, Erigeron strigosum, Vaccinium corymbosum, Rumex verticillatus, Alopecurus aristulatus, Carex festucacea, C. stipata, C. stellulata, and one belonging to the group Vesicaria, which I have not been able to determine, Sisyrinchium bermudiense, Orchis spectabilis, Geranium Robertianum, in the woods, quite wild, carpels much wrinkled, glabrous; Anemone virginiana. Of the last I find, in different localities, forms with larger cylindrical heads of carpels, and secondary pedicels without involucels; but the sepals are usually obtuse, and I am doubtful whether we have the true A. cylindrica (Gray), in Canada. Phlox divaricata was abundant, but out of flower, and Hydrophyllum virginicum also bore its fruit heads, shaggy with bristles. Asarum canadense was observed in one or two spots. Amphicarpaa monoica showed its long trailing shoots in the herbage of the woods. Of ferns, Dicksonia punctilobula was the most striking, and a singular lax form of this species, with dark foliage, was observed. Botrychium virginicum was very fine in dense beechen shades; Equisetum hyemale and E. limosum, both simple and branched, grew on the banks of the stream, the last usually in water.