General Jfotices. oil 



herbaceous and arborescent ferns, the latter of extraordinary altitade, 

 and Lycopodiacea?, an order now dwindled down to a few diminutive, 

 moss-like plants, but which, it is thought by Brongniart, reached at that 

 time the stature of our tallest forest trees. Associated whh these, are 

 found the first Conifene and Cycadacea;, which compose a very consid- 

 erable proportion of the flora of those remote ages, being probably the 

 next advance in the ascending scale of vegetable structure. In the 

 ferns and other flowerless plants, we find the reproductive organs either 

 obscure or imperfect; and in the next succeeding step, (the Coniferae 

 and Cycadaceje,) those organs, though distinctly characterized, are still 

 formed in the most simple manner, and accompanied with a correspond- 

 ing simplicity in the structure of the wood, the leaves, and the whole 

 vegetable system. As also we perceive the remains of the carnivorous 

 and lacustrine mammalia succeeding in a later formation to those of the 

 more primitive animals, so we find the palms, some of the Liliacea?, 

 and many Dicotyledonous plants, gradually assuming their respective 

 places, just as the improving condition of the globe became more fitted 

 to their respective organizations. In this way the history of the earth 

 is unfolded to us; and such are the proofs perpetuated and unchanged 

 through centuries of time, which show that it is through successive 

 ages, and by a slow and gradual series of changes, that the globe has 

 acquired its present more perfect state; and that both departments of 

 organized matter have advanced with equal steps and nuitually depen- 

 dent relations to that condition (perhaps still progressive,) in which 

 they are found at the present moment." 



MISCELLANEOUS INTELLIGENCE. 



Art. I. General Notices. 



Influence of Vapor on vegetation. — Messrs. Edwards & Colin have 

 read, at the Academy of Sciences, a third memoir on the influence of 

 vaj)or on vegetation. They observed, first, that the grains of winter 

 wheat did not germinate in air, because they were not saturated with 

 moisture; but that the germination, which, where the grains are satu- 

 rated with moisture, takes place in about eight days, happens in from 

 sixteen to twenty-four hours, if the grains are partly plunged in water. 

 From much experience, they have discovered that a temperature nearly 

 constant, (for example, that of a cellar of 50'^ Fahr.,) is better for ger- 

 mination than a more elevated, but variable, temperature, since the 

 variation of temperature prevents the air from being constantly satura- 

 ted with moisture. It is worthy of remark, that the grains al)sorb more 

 water in the latter case than when exposed to the uniform temperature 

 of a cellar. There are two conditions necessary for germination to 

 take place in the air; first, a certain proportion of water in the grains; 

 and secondly, that the air surrounding them be in a peculiarly moist 

 state. 



In air thus charged with moisture, the grain connnences by absorbing 

 water; and, when it has absorbed a sufficient quantity, if the tempera- 

 ture is constant, the air, still saturated with vapor, keeps the external 

 membrane in a state of humidity favorable to vegetation. If the hu- 



