are in the solid bottom, and the top of it is about the level of high tide. The top is square, as if cut off by an axe, and the longest time since it was cut can be little more than one hundred and fifty years. And when alive it must have been not less than three feet higher than now, to be out of the way of the tide. Judge Brick, of Port Elizabeth, says the tides have advanced a foot within fifty years-which, it will be perceived, agrees with the evidence to be obtained from the stump. Many persons have been disposed to estimate the rate of subsidence higher than this-but, in general, the statements are rather from impressions than from any fixed marks to refer to. I am confident, however, that two feet in a hundred years, is not above the rate at which the shore is now sinking.

From some facts collected, it would appear that the change on our own shore, is not confined to southern New Jersey. In the salt marshes on the Raritan, between New Brunswick and Perth Amboy, buried wood and stumps are common. Some years since a canal was dug across the marsh, from Washington to French's landing, to cut off some of the bends in South river, and the Raritan. The marsh cut through was from one to four feet deep, with a sandy bottom. Hundreds of stumps of the common yellow pine of the country, were found with their roots still firm in the sand as they grew; and though most of them were removed, a few are still to be seen at low water. The general impression at Washington is that the tides are fuller now than formerly. The marshes at the mouths of the Passaic and Hackensack are well known to contain great quantities of buried timber, and it is but a few years since they were covered with cedar trees. The same is true of the marshes on the shore of Long Island. Prof. Hitchcock, in his report on the Geology of Massachusetts, gives accounts of buried wood, erect stumps and peat, being found in the sea, at or below lowwater mark, as at the harbor of Nantucket, at Holmes Hole, on Martha's Vineyard, and also near the southwest extremity of the same island. They are seen too on the north side of Cape Cod, also opposite Yarmouth, and in Provincetown bay. Mr. Lyell, in his second visit to the United States, mentions a submerged forest "at Hampton, on the way from Boston to Portsmouth," also one near Portsmouth, N. H., 66 now submerged at low water, containing the roots and upright stools of the white cedar, showing that an ancient forest must once have extended farther seaward." In his First Visit to North America, vol. ii, p. 143, he mentions a submerged forest somewhat similar near Fort Cumberland, in Nova Scotia. In the same work, vol. i, p. 131, in speaking of the coast of Georgia, he says, "I even suspect that this coast is now sinking down at a slow and insensible rate, for the sea is encroaching and gaining at many points on the fresh water marshes. Thus at Beauly, I found upright stumps of trees of the pine, cedar and ilex, covered with live oysters and barnacles, and exposed at low tides; the deposit in which they were buried having been recently washed away from around them by the waves." He records other observa. tions in relation to the submerged trees at the mouth of Cooper river, near Charleston, and of the Altamaha, in Georgia. He quotes Bartram, the botanist, who wrote in 1792, as saying, "It seems evident even to demonstration, that those salt marshes adjoining the coast of

the main, and the reedy and grassy islands in the rivers, which are now overflowed at every tide, were formerly high swamps of firm land, affording forests of cypress, tupelo, Magnolia grandiflora, oak, ash, sweet bay, and other timber trees, the same as are now growing on the river swamps, whose surface is two feet or more above the spring tides that flow at this day. And it is plainly to be seen by every planter along the coast of Carolina, Georgia and Florida, to the Mississippi, when they bank in these grassy tide marshes for cultivation, that they cannot sink their drains above three or four feet below the surface, before they come to a strata of cypress stumps, and other trees, close together as they now grow in the swamps."

Analyses are given of various clays-one of a South Amboy fire clay which is used for facing paper-hangings, others of pottery clays, &c. Prof. Kitchell describes the crystalline rocks which prevail in the northern portion of the state (incorrectly called Azoic, as they are not of the Azoic age, although without fossils in consequence of metamorphic action), and gives many valuable details respecting the mines of copper, zinc, and iron. To this portion of the volume there are con tributions from the results of Mr. Wurtz, the chemist to the survey, relating to the mines and their ores and other minerals. alogical facts we propose to cite from, at another time.

The miner

The volume is illustrated by many beautiful engravings of scenery, representing landscapes in New Jersey, its lakes, mines, cedar swamps, etc.; and there are also some woodcuts, a map relating to the triangu. lation of the state, and another map of one of the mining regions.

4. Geological Survey of Missouri.-The first and second Annual Reports of the Geological Survey of Missouri, were announced in a former number as issued in a single octavo volume by the state geologist, Prof. G. C. Swallow, under the auspices of the legislature. We mention the reports again, to express our high estimate of the volume, and our earnest hope that a work so well begun may be carried on to its end. They are only the annual reports, not the final work; and we are free to say that none of the annual reports of our various surveys have come out in a manner more creditable to the authors or state, none in fact have equalled it in style of publication and illustrations. Some points no doubt remain for correction through future investiga tions, as happens in all such unfinished surveys, but, with few exceptions, the results appear to be carefully obtained as far as we can judge without going over the ground itself, and with judicious attention to points of geological interest, as well as to the best welfare of the state. The vast mines of iron, and those of lead, copper, and zinc, present the strongest inducements to a continuation of the work, regarding only its economical importance.

Prof. Swallow is aided in the survey by Dr. Litton, as chemist, who has in the volume a valuable report on the mines, with numerous analyses of ores and limestones; also by Dr. Meek, Mr. Hawn, and Dr. Shumard in the geology and palæontology.

5. Pseudomorph of Smithsonite.-We are informed by Mr. W. J. Taylor of Philadelphia, that he has observed at the Lancaster zinc mines, Pennsylvania, beautiful pseudomorphs of Smithsonite having the form of dolomite.

III. BOTANY AND ZOOLOGY.

1. For what purpose were plants created? (addressed to Prof. DANA.) -Plants furnish all the food upon which animals live. Plants, by decomposing carbonic acid, &c., purify the air which animals breathe. In which of these offices may we say that the vegetable kingdom fulfills its essential purpose? In your admirable exposure of the character and tendency of Prof. Tayler Lewis's work, you take the view that the essential object of the vegetable creation is to purify the atmosphere for the breathing of animals, and assert that its use in providing food for animals is only incidental, or concomitant.'

May I venture to question this; and to remark that I have been accustomed to consider the opposite view as the more correct and philosophical. I think also that it would answer equally well the purpose of your argument. It is just because that general argument is so sound and able, and because it proceeds from such very high scientific authority, that I am induced to call your attention to this questionable point, not without the hope that you may see cause to correct or qualify the statement.

That the office of plants in the economy of the world is, not so much to purify the air for animals, as to supply them nourishment, may be argued,

1st. From the nature of the operation in which oxygen gas is liberated by vegetables. Plants take carbonic acid, water, &c., from the air, and decompose them, giving back to the atmosphere a part of the oxygen, while they transform the rest of the materials into vegetable fabric, or into vegetable products (mostly the prepared materials of vegetable fabric). The raw materials used contain more oxygen than the vegetable matter produced from them does. The surplus oxygen has to be eliminated, and is therefore given off in a free state. Which appears to be the essential thing here:-the formation of vegetable fabric, or of organic matter, by which alone the plant can grow, from its parts, and continue to exist; or the evolution of the oxygen gas necessarily separated in the process, and which has to be got rid of?

It is in this deoxydizing and organizing operation, no doabt, that the essence of vegetation consists: but, that the great purpose is the organization, rather than the elimination of oxygen, and that the uses the latter may subserve (however important) are only contingent or 'concomitant,' may be further inferred,

2d. From considering the kind and the degree of the dependence of the animal creation upon these two results of vegetation, namely, the vegetable matter produced, and the oxygen gas liberated. Now, upon the first, as is well known, the dependence of the animal creation is entire and absolute: upon the second only remote and contingent. For vegetable matter, so produced furnishes the whole food and fabric of animals. Without it animal life could not have existed at all; and were its production now to be suspended, all the herbivorous and then the carnivorous races would perish almost at once. On the other hand, the amount of the dependence of animal life upon the disengagement

of oxygen gas by plants may be estimated by supposing existing vegetation to cease evolving free oxygen, or (which would come to the same thing) by supposing some new operation in the organic world to absorb this element as fast as it is given to the air by plants. How soon would the diminution of the oxygen of the air be felt even by the higher classes of animals. Making the needful calculations, M. Dumas has answered this question, by assuring us that the unbalanced action of the whole animal kingdom for a century would not consume more than go part by weight of the oxygen of the atmosphere ;-" a quantity altogether inappreciable to the most delicate means of investigation we possess at the present day, and which very certainly would have no influence on the life of animals,"-that, as respects the higher races of animals, "it would require no less than 10,000 years before all the men on the face of the globe could produce an effect which should be sensible to Volta's Eudiometer, even supposing vegetable life to be extinct during the whole of this time;"-so vast is the original stock of this important element of the atmosphere.

Surely, then, we ought not to call this remotely needful action upon the air the essential office of vegetables in the economy of the world, nor view as a subordinate or concomitant end that operation of organizing matter, which provides the whole animal creation with sustenance, and the failure of which for a single year would depopulate the earth. Nor should we call that the essential office of vegetation which certainly was not essential (as the other was) to the existence of an abundant animal life before and during the epoch of the coal-formation, and which (however propitious) has not been proved to be necessary even to the existence of man.

Of course there is no question here of this as a function of vegetation, and of the reciprocal action of the two kinds of organized beings upon the air, as maintaining the balance of its elements; but even here it is not always considered that, as Sir Boyle Roche once said, "the reciprocity is all on one side ;"-that though the animal kingdom could not exist at all without the vegetable, yet the vegetable kingdom might very well exist and flourish without the animal.

In other words, the vegetable creation is a provision for the animal, immediately and continually essential in one respect,-remotely and contingently needful-possibly essential to its well-being, but not to its being, in the other.

A. G.

Additional Note by J. D. Dana.-My meaning was this, that the whole structure and physiology of the plant was based on the great fact referred to, or its mode of living; and that this principle therefore, rather than the purpose of feeding animals, was that which in a sense determined the structure in this kingdom of life.

2. Researches on the Foraminifera: Part I, General Introduction, and Monograph of the genus Orbitolites; by WILLIAM B. CARPENTER, M.D., F.R.S., F.G.S., &c., (Ann. Mag. Nat. History, vol. xvi, p. 207.)-The group of Foraminifera being one as to the structure and physiology of which our knowledge is confessedly very imperfect, and for the natural classification of which there is consequently no safe basis, the author has undertaken a careful study of some of its chief typical forms, in order to elucidate (so far as may be possible) their

history as living beings, and to determine the value of the characters which they present to the systematist. In the present memoir, he details the structure of one of the lowest of these types, Orbitolites, with great minuteness; his object having been, not merely to present the results of his investigations, but also to exhibit the method by which they have been attained; that method essentially consisting in the minute examination and comparison of a large number of speci

mens.

The Orbitolite has been chiefly known, until recently, through the abundance of its fossil remains in the Eocene beds of the Paris basin; but the author, having been fortunate enough to obtain an extensive series of recent specimens, chiefly from the coast of Australia, has applied himself rather to these as his sources of information; especially as the animals of some of them have been sufficiently well preserved by immersion in spirits, to permit their characters to be well made out.

As might have been anticipated from our knowledge of their congeners, these animals belong to the Rhizopodous type; the soft body consisting of sarcode, without digestive cavity or organs of any kind; and being made up of a number of segments, equal and similar to each other, which are arranged in concentric zones round a central nucleus. This body is invested by a calcareous shell, in the substance of which no minute structure can be discerned, but which has the form of a circular disk, marked on the surface by concentric zones of closed cells, and having minute pores at the margin. Starting from the central nucleus,-which consists of a pear-shaped mass of sarcode, nearly surrounded by a larger mass connected with it by a peduncle,-the development of the Orbitolite may take place either upon a simple, or upon a complex type. In the former (which is indicated by the circu lar or oval form of the cells which show themselves at the surfaces of the disk, and by the singleness of the row of marginal pores), each zone consists of but a single layer of segments, connected together by a single annular stolon of sarcode; and the nucleus connected with the first zone, and each zone with that which surrounds it, by radiating peduncles proceeding from this annulus, which, when issuing from the peripheral zone, will pass outwards through the marginal pores, probably in the form of pseudopodia. In the complex type, on the other hand (which is indicated by the narrow and straight-sided form of the superficial cells, and by the multiplication of the horizontal rows of marginal pores), the segments of the concentric zones are elongated into vertical columns with imperfect constrictions at intervals; instead of a single annular stolon, there are two, one at either end of these columns, between which, moreover, there are usually other lateral communications; whilst the radiating peduncles, which connect one zone with another, are also multiplied, so as to lie in several planes. Moreover, between each annular stolon and the neighboring surface of the disk, there is a layer of superficial segments, distinct from the vertical columns, but connected with the annular stolons; these occupy the narrow elongated cells just mentioned, which constitute two superficial layers in the disks of this type, between which is the intermediate layer occupied by the columnar segments.