Page:Science vol. 5.djvu/304

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IToL. v., No. lis

��with tlic aitlhor. It caunut fail lo fastiunte the youthful etudent in the kindergarten. It has long been maintained that the elements of some of the sciences might be taught with ad- vantage iu the kindergarten. It remained for the inventor of this system lo sliow how readily this mav be done. Tbo ex^xanse is a mere trifle, and no preparation on the part of the teacher is required. We shall soon lind our children making marsh-gas. or etheue dibro- mide,' or showing how nitrate of [lotassiiim and sulphuric acid are converted into nitric acid and bydric potassic sulphate; wc shall hear them making the Dne distinction between plain water and cracked-up water; and we shall be obliged to confess that the method by which we were taught the elements of chemis- try was a verj- cumbersome one as compared with the simple method of Mr. Fanner.

While fully recognizing llic humorous fea- tures in the kiudei'garteu system of chemistry, we cannot avoid a feeling of depression wheu wo regard it as evidence of a stale of mind which is very prevalent. Too many teachers of chemistry, like Mr. Farmer, magnify the importance of formulas, nud lose sight of the facts which they represent. This is the crying evil in chemical iustniction at the present time. The teacher who "knows the theory,' but doesn't ' know the practical side of the sub- ject,' is still abroad in the land.

��Ti[t!< work is one of the smallest of this scries ; but it is one of merit and importance. Although the number of fossil plants from Vir- ginia strata hei-e cnumernted is not great, they arc so thoroughly illustrated, and so critically discussed, that their diagnostic value is fully brought out. Professor Fontaine may fairlj' claim to liave demonstrated, from evidence fur- nished by the plants alone, that these older mesozoic beds, which had not previously lieen clearly distinguished from the younger ones, and bad been commonly grouped with the lat- ter as the trias of Virginia, can scarcely extend so low as the extreme upi>cr trias, and conform more closely to the rhaetic of Franeouia, Bay- reuth, and I'alsjti, or even to the lias of Rajma- hal.

This conclusion, of course, is derived from

��an analysis of the S|iecics discovered, and a study of their affinities with species obtained from strata in other paru of the world, whose geological position is fixed with some degree of accuracy. This subject is discussed at length. The substance of it can be given in a fen words.

The whole number of distinct plants de- scnbed is forty-Bve. Eight of these were already known from other localities under tablished names ; four more of this class are referred to dilferent genera or sijeciea : mak- ing twelve not conlined to Vii'ginia, Of the remaining thirty-three which are so confined, nine have close affinities with species already described. It thus appears that considerably over half of the entire number are peculiar to the locality, and have no weight in determin- ing its liorizon. The decision must therefore turn entirelj- u[)on the twenty-one species which are either themselves found outside of Virginia, or are nearly allied to such as are so foimd.

The author has made some eiTors in )iis table of distribution, such as the omission of Schizo- neura planicostata, which be describes in the text, and the failure to assign Ctenophyllum Brauoianum to its proper horizon (rhaetic). These corrections made, we find that while only one of the species (Aaterocarpos platy- raehis) has its nearest alliuily with an exclu- sively triassic plant, and only seven have their nearest alfinities with exclusively Jurassic plants, there ai-e ten which bave either been found in the rhaetic only, or are most closely allied to such as have only been so found. Thus thirteen species, or about live-eighths, may be classed as rhaetic jilants : and only four, or less than one-fifth, can at Iwst be set down as triassic. The seven .lurnssic species are mostly from the lias, or lower oolite, which, while not negativing the riiaetic character of the Vii^inia beds, docs seem, whein coupled with the rest of the evidence, to negative their triassic character,

We have not space lo go further into details, and will merely add. that, while our analysis of his facta differs slightly from that made by I'rofeesor Fontaine, the conclusion whioh flows from it is the same ; viz.. that in so far as fos- sil plants can Ik de[iended upon lo correlate the de[jQBit8 of different parts of the world, thoai ' of the Richmond coal-fields point to the rhsetje of Kurope as the age to which they must bo referred.

It is something to have even thus far fixed the geological (tosition of this hitherto unset- tled formation : but those who arc specially interested iu the progress which is tjiking placa

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