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its catkins, and not rarely the early-blooming Crowfoot shows the blue tips of its clusters of blossom. March boasts a richer Flora; then the Violet delights us with its fragrance; the Mezereon offers its peach-coloured flowers, and the Primrose leads on a long train of the charming children of Spring. These now continue to advance in increasing numbers, displaying, especially in May and June, their highest splendour; till at length the Meadow Saffron takes leave of inclement Autumn, and, saturated with rain, the Mosses acquire fresh vigour, and open to the botanist a new field for investigation.

Not less different than the period of flowering is the time of the opening and shutting of flowers. Some plants habitually open and close their flowers by turns; others arc governed in these respects by the weather; others again, by the length or shortness of the day while some open and shut at certain hours, and thus furnish materials for composing the Dial of Flowers.

According to the observations of later botanists, the flowery crown of plants serves, among other things, to envelop the tender organs of fructification, and to protect them from the pernicious

influence of external agents. Those organs of fructification are the chief objects of the maternal care of Nature; while shut up in the flower-bud, they acquire that strength and perfection of parts which enable them to endure the light of the sun, and to perform the functions for which they are designed. It is not till they are capable of fulfilling these functions that the flower unfolds itself; but it again closes at such times when external influences might be injurious to the delicate organs of fructification. Many flowers can bear only the refreshing morning air and the first rays of the sun, but remain shut all the rest of the day. This may be particularly observed in the different species of Convolvulus, Ipomea, and Goat's Beard. We find these in general open only till about eleven o'clock. In like manner, the Mallows and the Mesembryanthemums unfolds their flowers about noon: and precisely at that time, in serene weather, open the singularly formed Drosera, and the common Purslain, which shut again in an hour. Others unfold themselves only in the evening, and continue open all night, probably because their delicate organs would be injured by the sun. The Enotheras, the Gauras,

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and the different species of the Mirabilis, furnish examples of this kind. Thus too the Cactus opuntia opens its magnificent blossoms at night only, and towards morning shuts them up for ever. The flowers of many plants of the nineteenth class are observed to hang their heads during nightthe Camellia, for example-by which means the rain, or dew, which might injure the tender organs of fructification, can run off the more easily. In other plants of this class, the flower shuts up against rain, and on the approach of evening, as is the case with the Marigolds.

The periodical change of colour in some flowers is also worthy of remark. Thus the flowers of the speckled French Honeysuckle (Hedysarum maculatum) are purple in the morning and green at noon. The changeable Hibiscus (Hibiscus mutabilis) is white in the morning, flesh-coloured at noon, and rose-red in the evening. Thus, to", the great Corn-flag (Gladiolus grandis) changes its colour several times in the course of the day.

Neither is the scent of flowers equally strong and agreeable at all hours of the day: many, even of our indigenous flowers, have the strongest scent at night. The Ixia cinnamomea gives out its fra

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DIAL OF FLOWERS.

grance in the evening only; the lighly-scented Lesser Orpine (Crassula odoratissima) only in the night; the Epidendrum fragrans, morning and evening; another species of Epidendrum, hung up in a room, without earth or water, yields an agreeable perfume for years. The flowers of the Hebenstreitia dentata are scentless in the morning, have a disagreeable smell at noon, and give out in the evening a fragrant odour, not unlike that of the Hyacinth.

These properties of flowers, and the opening and shutting of many at particular times of the day, led to the idea of planting them in such a manner as to indicate the succession of the hours, and to make them supply the place of a watch or clock. Those who are disposed to try the experiment may easily compose such a dial by consult. ing the following table, comprehending the hours between three in the morning and eight in the evening.