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    ;ggG TUM I/EADEB. [Satidkd4if,

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    Si'ontanuons (Jflnkkatton. Noportsmadc T...

    " 2 . Light has a very * great influence on the process of equivocaVgeneration . Thus , the green matter of Priestley , which is remarkable for its property of exhaling oxygen , is produced only under the influence of light ; when water , particularly spring-water , is exposed to the sun in transparent vessels , whether open or close , this matter appears in the form of a greenish cru $ t > consisting of round o . r elliptic granules , in which crust at first the slight mqtions of single moleoules are discovered , and afterwards transparent threads moving irregularly . These changes have been most fully observed by Ingenhouss . According to Professor Ji . Wagner ,, tlie green matter of Priestley consists of the remains -of green aqimqlcmies , the , eUgleha viridis ^ nd others , which have died . In that , case the moving . threads would Ibe independent beings , distinct from the green matter , and Ingenhouss would have committed the error of regarding different fcnids of pimple beings , ? , S' different states of the same molecules . . ¦ ¦ ¦ ¦ :. /

    ' " 3 . The entozoa and the spermatozoa , bodies with taife and spontaneous , motions , which are seen by the microscope in the seminal fluid , even pf invertebrate anipaals , seem to afford arguments for the spontaneous origin of living beings in organic matter . , . ..,, ¦ - ¦ •¦ nn ¦' ¦ " 4 . Treviranus found in- ' his own experiments that , under circumstances ptherwiee similar , different organic beings , namely , infusoria or mould , are formed , in different infusions ; and he found that , these differences did not depend ou the water , but on the substances infused , in it . / : .: . _ .. •< " 5 , Treviranus observed thai in ¦ one and tlie . $ am & infusion' , under different accidental conditions , different animalcules were developed j thus , from an infusion

    of the leaves of the iris with fresh spring-water , in . a long vessel covered . with linen , and exposed to the sun , infusory animalcules were , generated ; , in another vessel , placed in another situation , the green matter of Priestley was formed . Thus also the products in the same infusion of rye with spring-water were different , when Treviranus placed a bar of iron in one of the vessels . This result seems £ o , & g ? ee with that of Gleditsch , who found that in separate portions of melon covered . with muslin , and placed . at different heights , the various living organic substances , namely , mould , byssus , and treineuEc , ware produced in different proportions . To this niiglit be added , that Gruithuisen states that he has found perfectly , different animalcules in infusions of pus and mucus . " ;

    This ponstantvariation of the result following variation of the condition , is what every sound biologist would expect to find , and is not so conclusive in favour of spontaneity as -usually thought by those who cite it in suppqrt , because upon the oogenetic hypothesis it is explained as a variation in the nidus which permits the development of the ova . But now attend . Dr . Burnett , of America , after showing that parasites of the human body confine themselves strictly to particular regions , as the JPcdicidiis capitis always in the head , JP . vestimenti always on the surface , I . inguinalis always about the groin ; also states that he has found vegetable parasites in the human ovwni I They belonged' to a species of conferva ? similar to the yeast plant . They appeared by triplets or twos , and were about one 4000 th of an inch in diameter . It is impossible to explain their presence as spores , for the spores wouldx . be too large to be deposited from the circulation by passing through the walls of the bloodvessels . ( American Annual of Scientific Discovery , 1851 . )

    In Canstatfs Jahres JBericht for 1851 , ( vol . i ., ) we find that Wittich , who had observed entozoa in the hen ' s egg , made some experiments which proved that they might have reached their position by endosmose ; but the known porosity of the hen ' s ogg prevents our applying this to the human ovum . To this may be added Dr . J . Leidy ' s discovery of cryptogamic plants growing from the entozoa inhabiting the small intestine ; and we would especially commend Erasmus Wilson ' s work on Mingworm , as well as his paper in the Philosophical Transactions , 1844 , on the ontpzoa of the hair follicles ; they bring very strong evidence to bear on this subject .

    When we find entozoa within entozoa , and the entozoa only produced in certain diseased conditions of animal tissues , the idea of spontaneous generation cannot but recur . It is true that the old loophole of a nidus remains for every one to escape through ; there is no preventing the pld objection , " May it not be that the spores , & c . P" except by retorting . " May it not be that the generation does spontaneously take place r " W « have certain views respecting cell-development , and the passago from the inorganic to the organic , which make spontaneous . generation a true explanation of many phenomena ; but as those views are not yet before the world , we must content ourselves with the discussion as we iiud it . —

    and that is eminently unsatisfactory , if we except Mulder ' s section . In tlie Vestiges , great stress is laid on an argument by ]) r . Allen Thomson— -namely , "that the animalcules which arc supposed ( altogether hypotlietically ) to "be- produced by ova are afterwards- found increasing their numbers , no ! , by that mode at all , but by division of thoir bodies . If it' 1 ) 0 tho nature of these creatures to propagate in this splitting or ftflHiparoufl manner , how could they be communicated i *> a vegetable infusion ? " The argument is null , unless it can bo shown that the animaleules _ do not come- from ova , which is the point at issue . Dr . Allen Thomson will , on re-consideration , remember thai tjiis iisaiparoun genera tion i « common to a class of creatures that do unenuivocallv spring from ova . * J i h

    Ihero is one consideration wo would submit to the upholders of oogeuoHiB , derived from a survey of the facts . We know that the parasites , whether vegetable or animal , are peculiar to certain localities , certain organs , certn / n conditions . Tim oinopota cclUtris ' found only in boor and wine , ( Jin tfpnj . fi of man in found only-in man ' s intestine tho hyriiltut of \ k (} liver in found only in tho liver of various irummmlia , the intestinal worms appear only in tlio intestinea , and die if removed from them ; they have , boon obrtemnl i | i the inkmlinvH of the embryo ( Mullor ); ' morif ; nuiniula Jmvo their peculiar eui ^ oa ; the tinea in found only in wool that lias been dressed , never in undressed wool , and the cn-nwrus ih found only ( iii . ilio bruin , wl ^ u" <» jt j ) rodii (! eHi "* ia « -gnr « , " ' *

    ^ / ^ s 7 >^*^ T ^ jM ! tf " ¦ Hurvcy of these facts wilji n viow to thoir significance in this r ~;/ ^ ,, . » ., y ^ JH ^ C j we are led to ono of three results . C- l ^'' ' ^ yjs . S /' ' QfoftB » . oiitozoa and vegetable parasitcB have beoti created subsequent to X ^ - ~ K 1 / 1 - % * # ? W ' " ol" J | I ' « ' » I « Msia . l disturbance for the purpose of incrouuiui ; his £ r ~^ ¥$£ * J- 2 j TLu peculiarities wo observe in the localisation of those crouturefc arp wJy ^ fevWrt

    merely peculiarities of the nidus in which , each species is developed the varieties in the species being the result of varieties in the nidus ; the same egg giving birth to various creatures under different developmen tal conditions . 3 . Spontaneous generation . To accept the first : to say that the entozoa were made subsequent to man , subsequent to disease , subsequent to the civilization which produced beer and wine , dressed wool , and built wine cellars , would be to play havoc with all our notions of man ' slater appearance on this planet ; while the arguers of " final causes" will bepuzzled at the purpose of specially creating a c & nurus to give sheep the staggers . .

    To accept the second would he as heterodox as to aeeept the third . For if you are to allow suck immense importance ; to ft conditions" as to admit tliat a change- in tfye nidus " will create a change in the speciesi ,:. you tumble headlong into , tlie midst of the D ^ velopmenti Hypothesis , whioh this hypothesis pf Spontaneous Generation is brought forward to support ! For ourselves we accept both the ^ second and third propositions just laid down , and will support our opinion with an abstract of Mulder ' s arguments : , ; ; " : i - It is an eternal mystery how molecules , organic and inorgtoie , unite to form substances—unite in different ways to form different results . It is just as great a mystery with the inorganic as with the organic ; only our preconceived notions of JLife make the differences Ijet any man try to conceive the production of a crystal , and he will find it just as impossible

    as to conceive the production of a cell ; a precipitate is as mysterious as a primitive fibre . The truth , is , the elements of the organie kingdom , oxygen , hydrogen , carbon , nitrogen , are susceptible of endless modifications of their primary forces—endless combinations—as we see in the in & rganic kingdom . Every change , however minute , gives change i of result i ; sibme of these combinations , we call inorganic , others Organic : words by which we desi gnate the varieties of the forces at work . That presupposed , we find the upholders of oogenesis and spontaneous generation only differ in terms , or can , at any rate , be made to agree . If we consider an ovum as ah

    organic molecule , or organic body made up of the four elements combined in various groups , then the dictum of Harvey , omne vivwm ex ov 6 , isno doubt true . It is true also if we mean by ovum , a determinate molecule : for the mites of cheese are peculiar to cheese ; and certain fungi are produced only from peculiar plants . But if the term , ovum be taken , as it usually is , in an erroneous and limited sense , to mean the germ of an individual organism produced by peculiar organs only—a germ in which the . future animal is pre-existent—then observation will not bear us out . The individual is not contained in the egg ; and Harvey was one of the first to show tliis .

    The supporters of spontaneous generation meet the supporters of oogenesis , and agree with them in saying that there are certain organic molecules capable , under fitting circumstances , of evolving something new , whence individual plants and animals may finally be evolved . Why may not cheese , for instance , be an aggregation of ova , or organic molecules , from which a mite may be produced as from the ovum of an insect P It cannot be denied that the existence of spermatic animalcules proves that animals or their germs gradually growing , by merely floating in a fluid ,

    may be secreted . The existence of entozoa points to the conclusion that they may be produced from organic molecules , as every organic globule of mucus , milk , blood , < fec , is produced . As the germs of the spermatic animalcules are secreted animal germs , so may the molecules of oasein be the ova of mites though they remain as casein . The ono idea does not exclude the other . An ovum and an organic molecule are identical : they consist of elements which arrange themselves under . various circumstances in various forms , attract other elements , incorporate tJiein ,, and unite into definite compounds .

    To these observations of Mulder we would fain add some more abstract considerations , did space permit . Where he suggests that cheese may be the aggregate of certain molecules , each of which is capable , under fitting conditions , of assuming an independent life aud development as a mite , lie is touching upon a speculation wo hope some day to lay beforo the reader with adequate illustration . We may briefly indicate its direction by saying that , whereas every organ , as well as every auimul , is composed of countless individual cells which have lost their individuality ]< im the association , we have only to suppose tho . association destroyed , and then tU »

    cell , regaining its individuality , is developed into a higher form , instead of remaining a portion of the tissue . It is from the qssopiati & n of a multitude of cells , which , otherwise , would have independent l \ fc , that more complex animals arc formed . The lowest types are cells which spontaneously divide ; the next stop is mi association of vollq ; tUo third i « a transformation of those associated cells into a tissue ; so that ,-the life becomes less and less independent in , tho associated cells , and moi'o and more collective .

    Jhit as the association may at any time and in any plaoo bo destroyed , and as the development of certain , ccdls in , tho livor , the brain , or the-intestine- may be accelerated hcyond tlie normal point o , f hoputu ^ cerebral , or intestinal development , an cntozoon may bo produced , at tlip . ^ XP OJiP 0 of the tissue , or a vegetable may be produced if tho development be less potent , and thus we have- staggers or ringworm , tapeworms or cancer . -II- may be objected , iind justly , to the fqre ^ oing , that , inasmuch a » wo presuppose ; ui ' organic tissue or blastema ior the production of . Uh > ho lants aud of

    p entozoa , we liaye not aided tfje cau ^ o ujwutaniffouH # « moration , because ; the oogenetic defenders might say omua mn ^ tpt pas vwv watrtlxiir position , and HpotitancoiiH generation domajxla tJ » uMho wnuttal or . . planto bo formed from the inorganic world . " V ^ e think ,, ] »> wovor , that Mulder's argument settles this portion of Hie subject . If tho organic mqleculp l >« but an arrof ngement' of dements of inorganic s ' nl > Httiriccfl , ail ' that i « hecaVd in , tlmttho coiiditioim for » Uch uirarrangomoiit- ^ tho synthesis ; bd present-Wt > believm wo have imoortninod what 'thiMc o «* hditiorta are ; but pf ^ ' ^ b < m > af ' ttH \ i ¦ i .

    The world is one hunmani , manifostation of Ijifo : JSfatitro knpws not tlie diatiiuitions niatlo byiuun , fo » Iuh convenience . Wo , for Our -p \ frpokcnt may wejtarato the inorganics from tho m-g'anuo , as we ( separate- tlio vetfptftblo i ' ronx the animal , uud auimulB fi-om oacli other , and , from nian . ; but WoJdflg

    ;Ggg Tum I/Eadeb. [Satidkd4if,

    ; ggG TUM I / EADEB . [ Satidkd 4 if ,

• Citation
  • Leader (1850-1860), Dec. 25, 1852, page 16, in the Nineteenth-Century Serials Edition (2008; 2018) ncse-os.kdl.kcl.ac.uk/periodicals/l/issues/cld_25121852/page/16/