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October 23, 185^] THE LEADER. 1021
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VIM,A(,'|<; LlFi: IN I'UiYl'T. Vil/agii ...
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Peitchaed's History Of Animalcules. A. H...
derstand this on being informed that lie , violating all Biology , declares ft Animalcules to be " organized , and the greater part of them ( probably 11 ) Kiqhly organized bodies . " The supposed existence in these simple a llular structures of organs so complex as gall-ducts , ganglia , eyes , & c . 9 aceom panied by any evidence of tlie presence of those tissues from rVicli such organs are formed , or of those functions which they subserve ) will make the Biologist stare ; but what-will he say to Ehrenberg ' s assertion ( p- 7 ) j that " the power of infusorial organization is shown in this exhibition of a complete mental activity 1 ! " We feel that it is only
necessaiT to make an allusion to so outrageous a proposition . To disprove it would be to insult the sagacity of the reader . It may serve , however , as a text for a sermon on " Observation . " Havino" satisfied himself that Infusoria are highly organized , Ehrenberg discovers " that " they do not sleep . " The enunciation of this discovery is instructive , because it places the fact only as a probability . " They appear to be ( as far as is yet known ) sleepless . " He would not be surprised , therefore , to find them sleeping ? Did he ever ask himself what sleep was ? Professor Owen , in his quiet way , thus disposes both of the " sleeplessness" and of the " volitional activity" of these infinitesimal creatures : —
' ¦ ' The motions of the Folygastrica have appeared to me , long watching them for indicat ions of volition , to be in general of the nature of respiratory acts , rather than attempts to obtain food or avoid danger . Very seldom can they be construed as voluntary , but seem rather to be automatic ; governed , by the influence of stimuli willrin or without tlie body , not felt , but reflected upon the contractile fibre ; and , therefore , are motions which never tire . We may thus explain the fact which Ehrenberg relates— -not without an expression of surprise—namely , that at whatever period of the night he examined the living Infusoria , he invariably found them moving as actively as in the day time ; in short , it seemed to him that thesejittle beings never slept . "
The way these " organs" are discovered is simple . Ehrenberg observes a motion and infers a precedent volition , not conceiving that it may be automatic ; he observes a red speck , calls it an eye , and having so called it of course assumes a nervous system , corresponding with it . " If no other proof than this could be obtained , " says Ehrenberg or Mr . Pritchard , speaking of the eye specks , " of the existence of a nervous system in fchese animated atoms , this might still be taken as a sufficient evidence of the fact . " Yes , by microscopists , not by biologists ; in the absence of any proof of a nervous system the notion of an eye existing becomes baseless ; but the eye is assumed , and from that assumption a nervous system is deduced . See how this is
done" The llotatoria are not considered to possess a true nervous system , but m many of the species , having eyes , there appears one or two masses attached to them , which JLhrenberg thin / as are similar to nervous ganglia and nervous jibrillce . The eyes vary in number ; they are usually of a red colour ; in some they are placed upon a ganglion , and are freely moveable beneath the transparent superficial envelope of the body . " Now what is the naked fact—what is tlioro presented in observation ? The Microscope shows red specks , loose aggregations of coloured particles—why assume them to be eyes P In the spores of the Algse there are spots precisely similar , yet who calls them eyes P But on this point hear Dujardin , whom Mr . Pritchard , with praiseworthy candour , quotes for his own refutation : —
" The ; sense of sight would partake more of the character of reality , if the colour of a speck without appreciable organization , without a . constant form or a precise contour , sufficed to prove the existence of an eye . But , for instance , in the JCii (// rna , which art ; particularly cited as characterized by such an organ , the red spot so regarded is excessively variable , sometimes multiple , at other times made up of irregularly aggregated granules . "Analogy , too , is inadequate to tlio solution of the question ; for , on descending Uu : animal series , to determine the nature of tlu ; coloured speck , wo havo to leap from the Daphnia : ( members of the Jinlomoslraca ) , with a moveable eye , repeating i » its composition that of Insects and Crustaceans , to animals presenting nothing but dill ' used coloured specks .
" Such spotH , whether in number or position , havo so little physiological import"nci ! in t | 1 (; IManariie , and in certain Annelidcs , that they are often not even to bo employed as an absolute specific character . In the . Itotateiriu , tho analogy with which is more especially insisted on , these ; pigment spots are , in some species , known ( o disappear from age , and in others to become more evident , in proportion t <> size or development of individuals : so that the learned niicrogruplicr of Berlin , in Iiik attempt to base the generic characters of these animals on the presence and iiiiniluT of tlu ; eyes , has been led to place ; in different genera , species very closely : '" it : < l , if not identical . Indeed , that a black or red colour is in general an attribute ; oCllie ) pigment of eyes , cannot be' a reason lor concluding an eye ; to exist , wherever tlie'ii' Is a , •( ., ! colour ; if so , inelced , we ; must nccorel them te > , sonu ; intestinal worms , ii < ' ]| as the ; Scolcx polgiuorphus , which has two reel spots em the neck ; te > the actiniin , which mo olleiiKtreweel with such spev . ks , and nlse ) to some bivulvcd mollllsICH .
" If the ability of tlu ; Infusoria to elim't their course through the ; liquid , and to l » u « iie their prey , be nppeiiled to in evieleme'e , it is certainly , in the ; lirnt place , ne-• VNs . uy („ verif y ' the reality of this faculty , which I think equally fabulous with all ' '•¦ lal . od concerning tlie instincts of these animals . Indecel , it would not even pre > vo "" ' ii'il specks ( o be eyes , since ; t fui greatest number of Infusoria supposed to he ; < 'i < lo \\ ,., l wi ( , i , H 1 |( . „ f 11 ( . uK , an . m Uant , e > f the ; m ; imel those which ele > posses * "" '"i . < lo not exhibit , thill , power in u higher degree : e > f envelopment . " W « ' <| uit > hen : ji , eonl , n > verny only cemniK'n ' ced hee- ; uiHe ; we ; deemed it "" t'l'iU to iiulicMte ; the * tliuigcrri of l . oo implicit a reliance on Mm " ohMervn ,-tie > im" of | , | ln micmscojHHl ,, who like- eve > ry oMier observer depemels on Jiia "ite ||( , e | U ; , | training more ; Mum oil IiIm eyes . It is tlie ; ininel and not the ; •' that wees , jim odd iMirdtf oftenu iterate . '" < "iNliii ^ uboul , for jiii <; xtnie-t ol ' g eMionil interest we : found thin , which t !(> i'v »\ s to ill ,, strain || 1 O j ( | ( , a HO of | cii expressed in these columns—Mm hnl »« Nil » ili | , y ofdntwiii" - demareaMiitf linen in Nature : —
"' xtiiiction . between . Infusoria , and other Minute- Animals and . Wants . — In ''! ' •¦ _ l > r < we ; nt H |; ite of knowledge ; , with ivspeel , to organic bodies , them are many ( '" "' "' lie's in the way e > f determining on mieh botiiielnrie-s as niny reduce them to U 'H de fined gnmps . Uven tho lino of eleniurciitiem botwocn nnhniiln nnel p lants ,
which , at first sight , might be supposed to bo so very broad and distinct , upon a more minute consideration , is not easily settled . Nor is this surprising , for if wo turn to inorganic nature , we find the chemist is equally at a loss to separate the two grand classes into which he divides those bodies : namely , —metals and nonmetallic substances . While , at starting , they offer no resemblance , yet , by slight gradations , the bodies of each division approach the other where charact ers arc still wanting to distinguish them . As examples , we may take , the metal Silieium , which is sometimes regarded as a non-metallic body ; while , on the other side ,
Iodine and Bromine resemble metals . In'the organic world , no difficulty is found in separating the mammals , birds , and fishes , from forest trees and flowering plants ; but , as we descend in each kingdom , the lines of demarcation become less strong and decisive , until at length no single character is sufficient to distinguish them . TIius , motion , digestive structure , composition , the products evolved , & c , taken singly , are of little avail in separating an animal from a vegetable organism . Kcceut researches have rather increased these difficulties . The fashion of the present day is to magnify the arguments in favour of vegetable life and physical motions , while those on the side of an animal existence are slurred over . It is , therefore ,
desirable to pause before offering an opinion , especially when every distinction hitherto proposed , is seen to vanish if rigorously tested . The organisms of a doubtful animal nature , are principally found in the families Monadina , Vibrionia , and Bacillaria , which are fully described in Part III . " 1 . Motion . This is an excellent animal character , where its voluntary and spontaneous nature can be clearly perceived , but in microscopic bodies , vision being obtained by one eye only , and that under unusual conditions , difficulties present themselves which do not occur in common vision . Again , the germs , or spores of minute Alga 3 , and other vegetable organisms , swim about in water until they find
a proper place for attachment , when they grow as a plant ; hence some naturalists have supposed that animal life is transformed into vegetable , as the name zoospores implies . ( See Vibrionia . ) The mollecnlar motions of Dr . II . Browne—namely , those seen under a deep magnifier in a drop of water , in which finely divided gamboge or other organic substances have been triturated ; these motions have been , compared with the spermazoa of animals and plants , which are now considered as physical motions only . The circulation or cyclosis in plants , so well exhibited in the Chara , have been compared with the motions-in the Closterina and Bacillaria , and hence they are only allowed a vegetable life . ( See M . Tlmret on the Zoospores of Algae , Ann . des Sciences 2 S at . S ienVe series Tom XIV ., 1 S 50 . )
" 2 . Cilia . The presence of these organs for locomotion , as a strong argument m favour of the animal nature of an organism , but alone arc insufficient , as the minute spores of some Alga 3 possess them . " 3 . Digestive Organs . The presence of a stomach would strongly tend to the establishment of an animal , but plants have becii discovered which possess a cavity for admitting water , ' and thus resembling a digestive sac in its simplest form . While if imbibition by the cuticle be admitted , the cells e ) f plants approximate very closely to animals . The difficulties , however , arc greatest in the Desmidiacea anil Dlamomacea , to which the reader is referred to for particulars . " 4 . Composition . Tertiary compounds are claimed for the vegetable , but the Chlamidomonas , whose animal nature is undoubted , is only a tertiary compound . The presence of nitrogen was , sometime since , excluded from the vegetable , but it is now known that several plants contain azote .
" 5 . Starch . The existence of the organic proximate clement , Starch , bus been much insisted upon as determining this question , indeed its almost constant presence in plants , renders it a desirable test ; but , in the doubtful animal organism , their minuteness and the nature of their coverings , render it difficult of application ; indeed , in those cases where it is nmst needed , as the Des ) uidie < e ( which see ) , it too often gives equivalent results . " G . The evolution of Carbonic Acid by Animals and of Oxygen ly Plants , has been proposcel fen- determining this point , but the Kuglana viridis , whose animal nature is admitted exhales oxygon , as do some of the : doubtful family Uacillaria iinel the Volve ) x globator , the latter , however , has lately been claimed by the botanist . " 1 . I Isual Organs . The existence of eyes would prove , beyonel dtmbf , the animal nature of an organism ; buttle red points e-onsielereel as eyes , which exist , in many of the l ' olygnstrie Infuse > ria , arc , by some : naturalists , imt aelmitteel as eyes , similar reel spots being observed in the spores of Alga " , are atldue-eel as cemfinnatory e » f this position .
" 8 . CoutractihiUly has been proposed as a lest . It applies only to i ho soft hot lied forms , but M . Tliuret nay a it is not peculiar to animals , but partaken also by the : zoospeires of Alga :. " ' ) . Multiplication lit / spontaneous division or fission . This lnetbetel ofine-ivase has been aehluced by Klirenbesrg , us evielence : of the : animal nature of the lJiicillaria ami other Infusoria , but , it is nehnit teul , that flu ; ( issipnrtms elivision of vegetable : cells is of a similar nature . "JO . The iie ) ii-oe : c , urn ; nce of tlevelopimmt , by conjugid . ' uni , has be-en latterly insist eel upeni as Ke : pnrating animals from plants , but , this disline-. tiem is now euicstiouetl . "The action of aee ' . tie itcitl iiuel e ) f eh'etricity , on these minute organisms , hu \ e bee-ii pre > pe > sctl as tests , but hitherto the re ' . sults have : be'en unsatisfae'tory .
"This uncertainty in distinguishing plants tremi animals , couple-el with the : observation e > f semu : peculiar plirneHneiiH in the pmeluction of speires in the : lower Algie , h'el those : distinguislu ; el naturalists , I Jn ^ vr ami K iitzing , and eit hers , to believe in Mm ; transition of some forms , from an animal to a vegetable : existence , eir vice ¦ versa . It , see'ined to Kiit / iug , that there : are : beings in whierh annual auel ve'ge'lahle lile are so inthnatedy blendeid , that , the kind of e-xiste-ne'e . nianitesteel , will elepcnel on the ) pmelemiinnneo of one or of the other , : mel ( his too , without a nevessary change e > f fbrni . " In ( 'oncliisit )!! we recommend Mi is j I iston / of I > ifi ( sori < ff A ni' nmlculcs us ji , rt' |> e : rl , e > ry of i ' mit-H juul vicwH which ceniM e > nl y ho ; j ; e > l , at b y twlon . sivo re . seare'h .
October 23, 185^] The Leader. 1021
October 23 , 185 ^] THE LEADER . 1021
Vim,A(,'|<; Llfi: In I'Uiyl't. Vil/Agii ...
VIM , A ( , '|<; LlFi : IN I'UiYl'T . Vil / agii Xv /< i in M / j / pt , with > S 7 r < . /<•// r . v of ( ho Haid . Hy ltii . yle < St . . John . In 2 voIm . ( 'liupimin ami I lull . In liis former work . Mr . Uayle ; St . rle > hn inl . rodiiccel uh 1 , o the ; < loine : i-iti <; circle ; e > f ji I jcviuitine' f ' n . inily ; in his present , \ ve > rk he : has tulie : n uh inlo Mm villa ^ e : s e > f . lO f ^ ypt , nnel hIiowii us iiiiiny nsiiccts of |)(> m , sm . iiI- life . lit ; has n . Hf . rfni / jf synipjiMiy wilh the IcIlAhs , snief p le-aels their e-jniso wil . Ii onriKvit <) lt > t | ii <») x : t ) ; mi < I cogent r < - ; i «<> j » iii <> - ' ''" ' <> '' iiillwe'iice ; of IVle ) liJunmed Ali , In . his mmmo al-tenipl , L <> inlrexlue-o l ^ uropcan ciyiliziiLion , ullhuu ^ h
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Citation
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Leader (1850-1860), Oct. 23, 1852, page 17, in the Nineteenth-Century Serials Edition (2008; 2018) ncse2.kdl.kcl.ac.uk/periodicals/l/issues/cld_23101852/page/17/
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