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properly nourished, again multiplied by self-division, and grew to the likeness of the parent-cells.

Those who still hold by this rag of 'pre-existence of germs, call all organic corpuscles or granules cell-gemmules,' and maintain that they are transmitted, sometimes becoming developed, sometimes lying dormant from generation to generation, independent, automonous, pre-existing from their primal miraculous creation, as descendants, like all higher forms of life of that one form of Natural Selection” into which life was first breathed.' Darwin grafts upon this modification of the old evolutional dogma* his provisional hypothesis of ‘Pangenesis.' (cccviii)".

In like manner the Evolutionists hold that every single-celled organism, torule, organic molecule, out of the body, arises from a pre-existent germ; and that such germs abound in the air, in the waters, or wherever any forms of living matter may happen to make their appearance.

* Studying under this belief the phenomena described in CXLII, I was led to regard all cells' or organic units concerned in development and repair as the prog. eny of the primary germ-cell in the ovarium of the mother, and to be in that sense

derivative. Save in the case of the hypothetical primordial created unit, such primary ovarian cell in the Aphis and all sexual organisms I regarded as impregnated. The derivative cells or organic units propagated themselves independently of direct sexual intercourse; but, that they should not be remotely or indirectly related to the act by which their seat, the developed organism, came to be,-in which organism, or its parthenogenetically propagated offspring, the 'cells' subsequently were formed,

,-was to me inconceivable on the then accepted hypothesis of pre-existence of germs' or 'omnis cellula e cellulâ.' Mr. Darwin, however, opposes to the above view the remark, “My gemmules" (=my germ-cells) are supposed to be formed quite independently of sexual intercourse, by each separate cell or unit throughout the body.” (CCCVIII'', ii, p. 375.) Yet, his provisional hypothesis of “pangenesis assumes that they ("cells,' cell-gemmules, units ') * are transmitted from the parents to the offspring” ib.). But how so (in sexual species), save as the progeny or outcome of the primary impregnated germ-cell in the mother, whence all subsequent development and cell-generation radiated ? Take any case in CCCVIII'', which ‘Pangenesis' is propounded to explain-and all the given instances of varieties, malformations, &c., are from sexual organisms-as e. g. 'when a stag is castrated the gemmules derived from the antlers of his progenitors quite fail to be developed.' (Ib., ii, p. 399): to each I should reply as to this case:-Such stag first existed as an impregnated unit in the oviducal ovum of the mother. By the spontaneous fission' or cleavage process' it must have existed as a mass of impregnated gemmules. Accepting the nonsense, that some of these gemmules were derived from the antlers of its parent, yet they are not less the progeny of the primary germ-cell which was formed within the ovarium of the female and was fertilized by the male. I fail, after every endeavor, to appreciate the fundamental difference' between Mr. Darwin's cell-hypothesis of 1868 and mine of 1849 (CXLII, p. 5–8). Both of them I now regard as fundamentally erroneous; in so far as they are absolutely based on 'pre-existence '-or "omnis cellula,' &c. No doubt, many cells or organic units are derived from pre-existing cells (vol. i, p. 625): the phenomenon of the pale or granulated blood-cells which suggested to me, in 1838, the idea of the genetic mode of formation of the ordinary blood-discs, is a true phenomenon: but such mode of formation is subordinate to a wider law. Under given conditions matter in solution aggregates and shows form; if inorganic as crystal,' if organic as

spherule': in the one the process is termed 'crystallization, in the other formifaction. If the large pale cell' was first filled by fluid holding organic matter in solution, the smaller granules or atoms it subsequently discharged might be the result of 'formifaction. It is at least a more simple, and I believe truer, idea of their origin than that which ascribes such origin to a mysterious genetic act under the name of 'proliferation.'—CCCVIII'', vol. ii, p. 374.)

6

§ 428. Nomogeny or Thaumatogeny ?+--- The French Academy of Sciences was the field of discussion and debate, from 1861 to 1864, between the 'Evolutionists' holding the doctrine of primary life by miracle, and the 'Epigenesists, who try to show that the phenomena are due to the operation of existing law. The analogy of the discussion between Pasteur and Pouchet, and that between Cuvier and Geoffroy, is curiously close. Beside the superiority in fact and argument, Pasteur, like Cuvier, had the advantage of subserving the prepossessions of the party of order' and the needs of theology. The justice of Jamin's summary, & awarding to the chemist the palm of superior care and skill both in devising and performing the experiments, and exposing the inferiority of the physiologist in polemical ability and coolness of argumentation, cannot be denied. Nevertheless, Pouchet is rapidly acquiring, in reference to the origin of monads, that position which Geoffroy Saint-Hilaire has taken in regard to the origin of species. It is a suggestive and instructive fact in the philosophy of mind and the history of progress.

Some rare instances, in every generation, are gifted with the faculty of discerning the light of truth through all obstruction : when its glimmer is of the feeblest their brain responsively vibrates through a barrier of beliefs, prepossessions, precise logic, across thickets of facts deemed to be rightly understood, athwart accepted laws' and principles, organized corps of the soldiers of science, public opinion, &c.; and these men never know when they are beaten and put out of court: happily, against all hindrance, they persist"e pur si muove.'

Pasteur by an ingeniously devised apparatus, collected atoms in the atmosphere, and described and figured them as examples of organized corpuscles, 'globules,' or the 'germs’ of living things, there floating:|| In a solution of organic matter, otherwise unfit for the development of life, the addition of some of these germs was followed by the appearance, in abundance, of its simple forms.

To the conclusion that the monads were the consequence, not merely the sequence, of the ensemencement,' it can be objected that the atmospheric atoms figured are not like the * vópos, law, yévw, root of yiyvouai, to 'become,' or come into being. θαύμα, miracle, γένω.

I cccxxxIV', pp. 442, 443.
CCCIX'', p. 25, Pl. I, fig. 1.

| Ib., PI. I, figs. 2–9. Ý Ib., “ quelques corpuscles organisées."—p. 28, Pí. I, figs. 2, 3, 4:—"tout-àfait semblables à des germes d'organismes inférieures.”—p. 37. Of the various well marked forms of ova or germs of lower organisms, I know not any recognizable in the figures above cited.

observed formified corpuscles by which bacteriums have been seen to be built up; and, that the chemical treatment to which they had been subject, in their extraction from the atmosphere, would be likely to destroy the vitality of fecund germs, if any were present. To the alleged absence of any organisms in the experiments which were calculated to exclude extraneous germs, and to unfit the infusion for the development of any it might contain, the graver objection applies, that the microscopic power employed by Pasteur in their search was insufficient. Dr. Child, * in experiments which seem to be as exclusive as Pasteur's, does obtain bacteriums, discoverable, at first, by a power of 1,500 diameters, and, once so seen, afterward recognizable by a power of 750 diameters: whereas Pasteur, in his quest, did not avail himself of a power exceeding 350 diameters, and consequently failed to detect the evidence of 'nomogeny,' under conditions as decisive as can be hoped in an attempt to prove a negative. Against 'panspermism,' or the dogma that animalcules of infusions come, invariably and exclusively, from pre-existing germs falling from the air, Pouchet records the results of experiments, conclusive or satisfactory from their simplicity and ease of repetition, and freedom from need of minute, ambiguous, manipulatory precautions.

A glass tube containing a filtered infusion is placed in the middle of a glass dish containing the same infusion : this stands in a wider dish of water in which a bell-glass is placed covering the vessels with the infusion. At the end of four or five days the tube-infusion has a thick film abounding with ciliate infusoria : the dish-infusion has a thin reticulate film containing only bacteriums and other small non-ciliate microzoaires. It is difficult to see how the germs of the one kind of creatures should have entered or become developed in the one vessel and entirely different kinds in the other.'I

I refer the reader to cccxii' and cccxxxv" for further analysis of the grounds of the disputants, and proceed to remark, that the illustrations of the process of development of a Parameciumş so closely resemble those of the ovarian ovum in Fish or Mammal, that either fig. 555 or fig. 416, vol. i. of the present work serves as well as those given by Pouchet, to exemplify it. The proligerous pellicle, due to the resolution into molecules of the primarily formified bacteriums and vibrios of * CCCXII!.

ť cccx", pp. 122, 135. cccxii", p. 101: paraphrasing Pouchet:—Si les aufs tombaient de l'atmosphère, comme le prétendent les panspermistes, il n'y aurait pas de raison au monde qui pût faire que, dans la méme portion d'air, l'éprouvette en soit constamment remplie et la cuvette jamais. Celle-ci même, à cause de sa surface bien au. trement étendue, devrait en récolter infiniment plus.'—CCCX'', p. 136.

8 cccx'', Pl. II, figs. 1-5. and CCCXI'', Pl. I, fig. 1..

infusions, answers to the molecular contents of the ovisac. In both instances the molecules or granules aggregate into groups forming spheroids more opake than the rest (as in fig. 555, A): as the aggregation and coalescence advances the sphere becomes more opake, more definite : then a clear line marks its inclusion within a membrane, analogous to a 'zona pellucida,' and proclaims its individualization (as in ib. B).

Next appears a clear nucleus, answering to the germinal vesicle (as in ib. c). Fission of the nucleus is followed by that of the monad, which may thus multiply itself within the primary envelope (Chlamydomonas, ccxlix, fig. 29), like the cleavage-formation of the germ-mass : ciliary organs are acquired in both instances, rotating the germ-mass in the mammalian ovum, and extricating the monad from its proligerous bed ; whereupon it revolves or darts along, a free animalcule, in the subjacent liquor of the infusion.

In neither instance is there any support, from observation, of the derivation of germ-mass or of monad by evolution out of a pre-existing cell : in both instances have the processes of epigenesis or building up ab initio been repeatedly seen and traced.

In the case of the ciliate infusory the following are the primary or preliminary steps in the formation of the proligerous pellicle, or · Burdach's mucous layer.' In the clear filtered infusion a slightly opalescent appearance precedes the formation of the thin superficial film. This consists of molecules of various sizes, the most minute testing the highest powers of the microscope. These molecules I attribute to the act of formifaction, which in reference to organic matter in solution corresponds with the crystalline aggregation of mineral matter in solution. Solution of organic matter, such as clear serum from a blister, inclosed in goldbeater's' skin or other close membrane, and inserted beneath the integument of a living Mammal-even distilled water which so placed obtains the elements of formifaction by endosmosis-shows its results in the form of granules, white blood-cells, pus-globules, &c. These experiments need repetition and modification mainly in reference to the objection that such leucocytes' might have wriggled their way, like Amcbæ, from without, through the close texture of the enclosing bag.† In the proligerous pellicle the larger molecules unite end to end, forming bacteriums, or less regularly into masses composing Torulo : these send out parts which become jointed tubes, and may terminate in rows of sporules (Penicil

* cocx', pp. 352–388. Cocxi'', pp. 133–253. CCCXII'', pp. 121–129. CCCXIII'', p. 1046. cccxiv', p 974. cccxv", p. 467: Mantegazza spent sixteen consecutive hours in observing this genesis.

+ CCXVII''.

lium) or capsules of such (Aspergillus) The bacteriums may, by further union and confluence, form vibrios. There is much activity, allied in character to the Brunonian movements ;* which, after a time, ceases, and the bacteriums, vibrios, &c., are decomposed to constitute the secondary series of molecules in and from which the development of the higher ciliate Infusory takes place. The formation of the proligerous pellicle or 'secondary histolytic mass of molecules’t by the primary developments and resolutions of the organic material, is analogous to the formation of the germ-mass, in ovo, by the successive spontaneous fissions, assimilations, and ultimate coalescence of the progeny of the original germinal cell.

To meet the inevitable question of Whence the first organic matter' ? the Nomogenist is reduced to enumerate the existing elements into which the simplest living jelly (Protogenes of Hæckel) or sarcode (Amoeba) is resolvable, and to contrast the degree of probability of such elements combining, under unknown conditions, as the first step in the resolution of other forces into vital force, with the degree of probability remaining, after the observations above recorded, of the interposition of a miraculous power associating those elements into living germs, or forms with powers of propagating their kind to all time, as the sole condition of their ubiquitous manifestation, in the absence of any secondary law thereto ordained.

In this, the last general summary of work which I am likely to find time to complete, the expression of belief on one or two points where proof is wanting may be condoned. The chance of its being a help, or encouragement to any younger, more vigorous mind, bent upon grappling with such problems, outweighs any anticipation of trouble consequent upon the avowal.

It seems to me, then, more consistent with the present phase of dynamical science and the observed gradations of living things, to suppose that sarcode or the 'protogenal' jelly-speck should be formable through concurrence of conditions favoring such combination of their elements and involving a change of force productive of their contractions and extensions, molecular attractions and repulsions-and that sarcode has so become, from the period when its irrelative repetitions resulted in the vast indefinite masses of 'eozoon,' exemplifying the earliest process of 'formifaction or organic crystallization than that all existing sarcodes or 'protogenes' are the result of genetic descent from a germ or cell due to a primary act of miraculous interposition. Some, accepting the latter alternative, teach that, while

* CCXVIN'', p. 470, in all organic molecules, living or dead. + cccxxxv'', p. 10.

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