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 98 on the germination of the Orchis tribe. We reserve more particular remarks on this subject till we examine the structure of seeds.

Some plants are reckoned by Linnæus to have many cotyledons, as the Fir and Cypress. But the germination of these differs in no respect from that of the generality of dicotyledones. Mr. Lambert, in his splendid history of the genus Pinus, has illustrated this peculiarity of structure in the Swiss P. Cembra; see our tab. 1. fig. 2. In the Dombeya, or Norfolk Island Pine, the cotyledons are very distinctly four: see fig. 3.

The preservation of the vital principle in seeds is one of those wonders of Nature which pass unregarded, from being every day under our notice. Some lose their vegetative power by being kept out of the ground ever so little a while after they are ripe, and in order to succeed must sow themselves in their own way, and at their own time. Others may be sent round the world through every vicissitude of climate, or buried for ages deep in the ground, till favourable circumstances cause them to vegetate. Great degrees of heat, short of boiling, do not impair the