searches is precisely that Mr. Pasteur's facts are inexact-not because his experiments were not most admirably performed, but simply because the magnifying power of his microscope was insufficient for the work to which he applied it. I desire to append two remarks to this paper. The first is, that the common à priori objection, which Mr. Pasteur so well expressed in his memoir, to heterogeny in all forms, viz. that it is a doctrine which has been gradually driven from all the higher forms of life in exact proportion as our observation of them has become more exact, until at last it has been compelled to take refuge in those lowest forms which we are almost or altogether unable to observe, is really of little or no force. Its cogency depends on analogy, and the analogy has no existence. It is quite equally to be expected à priori that if any forms of life are generated spontaneously, they will be the very lowest and simplest forms, and since these happen to be also the most minute, the objection loses its whole force. And it is also a thing to be expected that we should find only the lowest forms, the earliest, i. e. in the scale of existence, produced under the disadvantageous circumstances in which they must be placed in such experiments as those above detailed.

The other remark is this: that, so far as my present researches have led me, I cannot but look upon improvement in the construction of microscopes, and increase of their power, as the only way in which our means of investigation of such questions as the production of Bacterium is likely to be largely increased. The object-glass recently constructed by Messrs. Powell and Lealand, of which a notice has appeared in the Proceedings of the Royal Society, has already shown something like an appearance of structure in these minute objects, and leaves, I think, no doubt about their organic character.

ART. XLVIII.—A word on the Origin of Life; by JAMES D. DANA.

THE notion seems to be somewhat prevalent that if such experiments as those described in the preceding paper by Mr. Child really afford examples of spontaneous generation—that is, of the production of living organisms without the intervention of germs they exemplify the process of the first origin of life. The claim made by Prof. H. J. Clark in the title of his recent work-"Mind in Nature, or the Origin of Life, and the mode of development of Animals"-to which we objected in the last number of this Journal, and which the body of the work endeavors to sustain, rests on no other basis. And his opinion of

the firmness of the foundation is shown by his taking one long step onward from this basis, as follows:'

The fact that the experiments with the sealed flasks proved-if anything can be proved beyond the reach of change or improvement-that beings with motion, undoubted living beings, were produced when life could not possibly have existed previously, is a sufficient basis for the further assumption that still higher forms could arise from these. That is to say, if, under the conditions in the sealed flasks, living beings, either animals or plants, of the lowest degree, arise, there is nothing illogical in assuming that, from these lowly organized, animate bodies, somewhat higher and more complicated beings may originate.

Now in the experiments referred to, and all of similar character, the experimenter starts with organic matter, either vegetable or animal. Allowing, then, that there are no germs present to breed such low organisms, the results are only examples of life from life; and to the question, what is the origin of life, they reply-life. For without some pre-existing plant or animal to afford the hay, or flour, or muscle, etc., there could have come none of the plants or animals bred by the alleged spontaneous generation. The world of such "creationists" would therefore have ever remained lifeless. Consequently, not the first stone is laid by these and like experimenters toward bridg. ing over the interval between the inorganic and organic world; not the first step is taken into the yet dark regions back of the existence of life on the globe.

The organic matter operated upon is in one sense dead; that is, the organism as a whole has not its living functions. But still it originated through life; and, moreover, the particles in the fibre of hay or muscle are held together, or remain as they are, in virtue of the forces which, in the processes of life, formed it; just as the particles of a drop of water are retained as they are by the forces-far inferior in kind and amountwhich made the combination water. When the decomposition of the material begins, and the forces are thus disturbed, then the moving things, claimed to be a spontaneous generation, make their appearance. From the compound of high order in the vegetable or animal kingdom-of high order no doubt chemically as well as vitally-comes the lowest in the vege table kingdom, a cellular plant consisting of one or a few cellules, or perhaps an equally low animal organism.

On page 26. We have already expressed our high opinion of the microscopical investigations by Prof. Clark, which constitute a large part of his work, and make it an exceedingly valuable contribution to zoological science.

The experiments mainly of Dr. Wyman, of which an account is given in the work at some length, are here referred to.

Prof. Clarke speaks of the Bacteria as probably related to vegetable mould; and, after a microscopic study of certain Vibrios obtained by Dr. Wyman in his trials, pronounces them also vegetable.

In view of these facts, that from life has come the new life, and from the high only the extremely low, the assumption, cited above, which makes the second grand conclusion of Prof. Clark, "that still higher forms could therefore arise from these," is certainly without even the shadow of a foundation. Such spontaneous generation does not begin to climb the hill of life; it looks downward and not upward.

The best statement which we have seen of the relation of the generated organism-supposing it a real generation without germs -to the original organic matter, is that made by the chemist Fremy to the French Academy, and which we have reproduced (translated from the French) into this Journal, in vol. xxxviii, at page 439 (Nov., 1864).

But the absence of germs, although seemingly possible, is far from being proved, as Mr. Child admits. The high temperature used in the course of the experiments on spontaneous generation is sufficient, it is true, to destroy the life of ordinary plants or animals, but it does not decompose the vegetable or animal material employed in the trials. And, considering the low order of the organisms that are developed, it cannot be assumed that heat which this material stands will destroy their germs.

The following observations, communicated to the writer by Prof. W. H. Brewer, the Botanist of the Survey of California, as well as Assistant in the Geological department, show that plants of low grade may thrive in waters very near if not at the boiling point, and even when strongly acid or saline.

Observations by Prof. W. H. BREWER on the presence of living species in hot and saline waters in California.

Dear Sir:-In answer to your request I can give the following facts regarding the occurrence of plants in certain thermal springs, and animals in certain saline waters, of California.

The (so-called) Geysers on Pluton creek, a branch of the Russian river, lie at an altitude of 1700 feet above the sea. They consist of numerous steam vents, and hot springs, of various temperatures, the hottest observed being 97° Ĉ. (about 207° F.).

The temperature of the steam in the larger vents was not observed. It issues from some of them with a noise as if released from considerable pressure. The waters contain a variety of salts in solution, apparently mostly the sulphates of iron and alumina; and efflorescences of sulphur, and sulphurous gases are abundant. From most of the springs the water is decidedly acid, discoloring the boots, gloves, and clothes of the visitor.

In these warm mineral waters low forms of vegetation occur. The temperatures were carefully observed in many cases. The highest temperature noted in which the plants were growing

was 93° C. (about 200° F.) But they were most abundant in waters of the temperature 52° to 60° C. (125° to 140° F.) In the hotter springs the plants appeared to be of the simplest kind, apparently simple cells, of a bright green color; but they were examined only with a good pocket lens. In the water below, about 60-65° C., filamentous Confervæ formed considerable masses, of a very bright green color.

Around many of the steam jets, on the soil, similar or identical plants formed a thin green coating, like Nostoc on wet surfaces. Here they were exposed alternately to jets of hot steam and cooler air. The highest temperature they were subjected to could not be observed; but the soil was hot, and as the steam was often "dry" and transparent, it was equal to, if not above, the temperature at which water boils at that altitude.

The specimens I collected were accidentally destroyed on our return trip; but later Messrs. Mann and Brigham collected specimens from water having a temperature of about 130° F. A part of these were placed in the hands of Dr. Jeffries Wyman of Cambridge, and Mr. A. M. Edwards of New York. The latter person states that he finds animal as well as vegetable organisms in the specimens.

At the "Little Geysers," a few miles distant from those last mentioned, and at an altitude of 2000 feet or more, the same phenomena were observed; but the altitude being greater, the waters were not quite so hot.

These observations were made in November, 1861, and the facts communicated verbally to the California Academy of Natural Sciences the following winter.

Plants occur also in various other thermal waters in the State. They were noticed in great abundance in water having a temperature of 122-125° F. in a warm spring in Owens Valley, about 35 miles above Camp Independence.

The celebrated Steamboat Springs, near Washoe Valley, in Nevada, are very extensive, and the waters hold much silica in solution, which is deposited as they cool. Where the water spreads out over the surface there is in places an abundant growth of confervoid vegetation in the gelatinous mass formed. This was most abundant where the temperature was about 100° F. or less, judging of the warmth of the water by the hand. The most interesting feature in this case is the abundant vegetable growth in the gelatinous silica.

In regard to the occurrence of animals in strongly saline waters, some facts are of equal interest. Mono Lake is intensely saline. The water has a very high specific gravity, and contains common salt, carbonate of soda, and borax, with other ingredients in less quantities. It dissolves grease easier than ordinary soap, and discolors certain woolens. It leaves a very

unpleasant smarting sensation on the skin, and feels soapy to the touch. Yet it contains the larvae of a certain species of fly in immense numbers. These are cast up on the shore at times in such quantities that a great stench is produced. These larvæ dried form an important item of food with the Mono Indians, who call it "Koo-chah-bee." The flies are seen in equally large numbers about the shores of the lake.

Similar flies are mentioned as occurring at the Great Salt Lake, by various persons. Lieut. Stansbury speaks of their immense numbers in his Report, but we have no facts as to their specific identity.

New Haven, March 26, 1866.

We append the following important note on the tenacity of life of the seeds and spores of some plants, prepared for this place by Prof. Brewer. Note by Wm. H. Brewer.-EDWARDS and COLIN (Annales des Sci. Nat., [2], Bot. I, 257) made experiments on the power of resisting ele vated or depressed temperature possessed by the seeds of various leguminous and cereal plants. They found that all lost their vitality if heated in water at 167° F., which is the temperature at which starch grains burst. The most of the seeds had their vitality destroyed when heated in water below this, but would stand a temperature of 122°; while in steam they would stand 144° F.; and in dry air some germinated after being heated a very short time to 167° F. Above this all lost their vitality. Some would stand a dry cold of 70° F. below zero.

Berkley states (Introduct. to Cryptogam. Bot., p. 68) that he has "recorded an instance of the germination of thousands of grape seeds after three immersions in boiling water; and Dr. Lindley mentions the fact of raspberry seeds growing after being boiled for jam, in which case, if the sugar were really boiling, the temperature would be above the boiling point of water." The author considers, however, that the observations were not sufficiently exact in either case.

Balfour states (Class Book of Botany, p. 628) "the seeds of Phytolacca decandra and of the Raspberry have been known to germinate after exposure for a short time to the heat of boiling syrup," but does not give his authority.

Hemmingway states (Ann. of Nat. Hist., [1], viii, 317) that the seeds of Sambucus nigra germinated after being twice boiled in making wine, being present during the vinous fermentation, and remaining twenty months in the dregs of the cask.

In regard to the spores of Fungi, Berkley remarks (Outlines of British Fungology, 32) "that the spores of certain Fungi would bear a moist heat equal to that of boiling water without losing their power of germination. They have also considerable powers of resisting frost, but the exact limits in either case under varying circumstances have not at present been ascertained."

More to the point are the experiments of the eminent cryptogamic botanist, Payen, on the red mould in the interior of bread, which created such a stir in Paris nearly twenty years ago. This mould, the Oidium AM. JOUR. SCI.-SECOND SERIES, VOL. XLI, No. 123.-MAY, 1866.