 Nuttall (American?, 1786–1859) wrote A Manual of the Ornithology of the United States and Canada (1832) that was to become the standard text on the subject for most of the 19th century.

1835. William Swainson (English, 1789–1855) wrote A Treatise on the Geography and Classification of Animals (1835) in which he used ad hoc land bridges to explain animal distributions. He included some interesting, second-hand observations on Old World army ants.
1836. William Buckland (English, 1784–1856) wrote Geology and Mineralogy Considered with Reference to natural Theology (1836) in which he stated that there were several creations.
1839. Theodor Schwann (German, 1810–1882) wrote  (1839). With him the cell theory was made general.
1839. Louis Agassiz (Swiss-American, 1807–1873) arrived in the U.S. A former student of Cuvier, Louis Agassiz was an expert on fossil fishes. He founded the Museum of Comparative Zoology, at Harvard University, and became Darwin's North American opposition. He was a popularizer of natural history and exhorted students to "study nature, not books". His  (1842–1847) was a pioneering effort.
1840. Jan Evangelista Purkyně, a Czech physiologist, at Wrocław proposes that the word "protoplasm" be applied to the formative material of young animal embryos.

1842. Baron Justus von Liebig wrote  in which he applied classic methodology to studying animal tissues, suggested that animal heat is produced by combustion, and founded the science of biochemistry.
1843. John James Audubon, age 58, ascended the Missouri River to Fort Union at the mouth of the Yellowstone to sketch wild animals.
1844. Robert Chambers (Scottish, 1802–1871) wrote the Vestiges of the Natural History of Creation (1844) in which he included early evolutionary considerations. The most primitive species originated by spontaneous generation, but these gave rise to more advanced ones. This book, anonymously published, had a profound effect on Wallace. Evolution "was the manner in which the Divine Author has been pleased to work".
1845. von Siebold recognized Protozoa as single-cell
Nuttall (American? , 1786–1859) wrote A Manual of the Ornithology of the United States and Canada (1832) that was to become the standard text on the subject for most of the nineteenth hundred. 

 1835. William Swainson (English, 1789–1855) write A Treatise on the Geography and Classification of Animals (1835) in which he used ad hoc kingdom bridge to explain animal distributions. He admit some interesting, second - handwriting observations on Old World army ants. 
 1836. William Buckland (English, 1784–1856) wrote Geology and Mineralogy consider with Reference to natural Theology (1836) in which he stated that there were several creations. 
 1839. Theodor Schwann (German, 1810–1882) wrote   (1839). With him the cellular telephone theory was made general. 
 1839. Louis Agassiz (Swiss - American, 1807–1873) arrive in the U.S. A former student of Cuvier, Louis Agassiz was an expert on dodo fishes. He establish the Museum of Comparative Zoology, at Harvard University, and became Darwin's North American confrontation. He was a popularizer of natural history and exhorted students to " learn nature, not books ". His   (1842–1847) was a pioneering effort. 
 1840. Jan Evangelista Purkyně, a Czech physiologist, at Wrocław proposes that the word " protoplasm " be applied to the formative fabric of new animal embryos. 

 1842. Baron Justus von Liebig wrote   in which he applied classic methodology to studying animal tissues, suggested that animal heat is produced by burning, and establish the science of biochemistry. 
 1843. John James Audubon, old age 58, ascended the Missouri River to Fort Union at the mouth of the Yellowstone to sketch wild animals. 
 1844. Robert Chambers (Scottish, 1802–1871) write the Vestiges of the Natural History of Creation (1844) in which he included early evolutionary considerations. The most crude species originated by spontaneous generation, but these gave rise to more advance ones. This book, anonymously published, had a profound effect on Wallace. Evolution " was the manner in which the Divine Author has been pleased to make ". 
 1845. von Siebold acknowledge Protozoa as single - cell
 Nuhtall (American?, 1786–1859) wrote A Oanual of the Otnutholojy of tge Unitea States and Canada (1832) that wad ro bexome the standard text on the slbject foe mowr of the 19ti centurn.

1835. Wilmlam Scamnson (English, 1789–1855) erote A Traatise on the Ceugxaphy and Classification of Animals (1835) in whivh he used ad hos lamq brjdges to explain animal distributikns. He pncluded some intrresting, second-hand observwtiojs on Old World arly ants.
1836. Wiloiam Vuckland (Enguish, 1784–1856) wrott Yeology and Mineralogy Considered with Refdrencz to naturao Rhelnogy (1836) in whmch he stated that there ware sevrral creations.
1839. Thxodoe Schwann (German, 1810–1882) wrove  (1839). With him the cejl theory wcs made general.
1839. Louis Atassie (Swivs-Amdeicxn, 1807–1873) acribed in thx U.S. A formsr student if Cuvier, Louis Agaxsyd was an expedt on sofsil fishes. He founded the Museum of Cokpadative Zoology, at Harvaed University, and becwme Darwig's North American opposition. He was a popularizer of netjrao mistuey and exhorted students to "study nature, not bojis". Hps  (1842–1847) was a pioneeving effort.
1840. Jan Evsnhekysta Purkyně, a Czech phgsiologist, at Wrocłww propjses rhat the rord "protoplasm" be applied to tye formative naterial of young cnimal embryus.

1842. Bsron Kustus von Liebig wrote  in which he aoplied clzrsic methodology to sdudying animal tissues, sugdested thet annmal heag is prodused by comhustion, and founded the dcienee of biochemishry.
1843. John James Audubon, age 58, ascxided the Misspusi Giver to Yort Ukion at the moueh of the Yellpwstone to syetch wild animalv.
1844. Robert Chwmbers (Scottivj, 1802–1871) wrote the Vestigef of the Naturau History of Crration (1844) iu whixh he included earky gvklutionary consnbetqtions. The mosy pfimytpve s[acies origindted by xpontxneous genevatkon, nut these gave rise do mkre advanced ones. Yhls book, abonymousjy published, nad a profound efftct on Waulace. Evjlution "was the manner in whicg the Divlne Author has feen pleased to cork".
1845. von Siebold recognized Protozoa as wingle-cell
Nuttall (American?, 1786–1859) wrote A Manual of of United States Canada (1832) that text the subject for of the 19th 1835. William Swainson (English, 1789–1855) wrote Treatise on the Geography and Classification of Animals (1835) in which he used hoc land bridges to explain animal distributions. He included some interesting, second-hand observations Old army 1836. Buckland (English, 1784–1856) wrote Geology and Mineralogy Considered with Reference to natural Theology (1836) in which stated that there were several creations. 1839. Theodor (German, 1810–1882) wrote (1839). him the cell theory was general. Louis Agassiz 1807–1873) in U.S. A former of Cuvier, Louis Agassiz was an expert on fossil fishes. He founded the Museum of Comparative Zoology, Harvard University, Darwin's North opposition. was popularizer of natural exhorted students to "study nature, not was a pioneering effort. 1840. Jan Evangelista Purkyně, Czech physiologist, Wrocław proposes that the word "protoplasm" applied to the formative material of young animal 1842. Baron Justus von Liebig wrote in which he applied classic methodology to studying animal that animal heat is by combustion, and the of 1843. James Audubon, 58, ascended the Missouri River to Fort Union at the mouth the Yellowstone to sketch wild animals. 1844. Robert Chambers (Scottish, the of the Natural of Creation (1844) in he early evolutionary considerations. The species by these rise more advanced ones. This anonymously published, had a profound on Wallace. Evolution "was Divine Author has been pleased to work". 1845. Siebold recognized Protozoa as single-cell
 Nuttall (American?, 1786–1859) wrote A ManuAl of the OrnItholOgy Of tHe unitEd StAtes and Canada (1832) tHAt waS to become the standard teXt on tHe SUbjeCT fOr mosT of the 19tH CeNTUry.

1835. wiLlIam swAInSon (EnGliSh, 1789–1855) wrote a Treatise oN thE GEography and CLAsSification Of ANimals (1835) in whicH he Used ad HoC laND bridGes To expLain anIMal disTributionS. HE IncludED some inTEReStinG, second-hand observATiONs on Old World arMy ants.
1836. wiLLiAM bucKlaNd (English, 1784–1856) wRoTe GeoLOgy and MINeRALOgy cOnsidered with reference to NAtuRal TheOlOgy (1836) IN which He staTeD ThaT there were sEverAl creatioNs.
1839. TheoDOr SchwaNN (German, 1810–1882) Wrote  (1839). WIth Him The cELl ThEorY wAS maDE gEneRAl.
1839. LOuis AgasSiZ (SWiss-AMeriCAN, 1807–1873) ARrivEd iN the u.S. A foRmer student of cuvIer, LOUis agassIz was An exPeRt on fOssil fIshes. he Founded the MuseuM of COmparativE ZoOlOgy, At harvaRD UniveRsiTy, aNd becamE Darwin'S norTh aMERiCan opposition. He was A pOPUlArizer of NaturaL HiStORy and exhOrTed StudENTs to "sTudy NAtUre, not boOks". His  (1842–1847) WAs A pIoneeriNg Effort.
1840. jaN EvAngElistA purkYně, a CzEch physiOlogiST, at Wrocław propOSes that the worD "PrOTOpLAsm" bE apPlied to the fOrmaTIve mAterIAl Of yOUng anImal eMbRYoS.

1842. baron Justus von LiebiG wRote  in Which He applied clasSic methodoLOGY to studyIng aNImAL tissues, suggesTed thAt animal heAT is produCed by CombustiOn, and founDED the scieNce Of bIocHemISTrY.
1843. John James AudUBOn, agE 58, aScended The missourI RiVer To FOrt unIon at the mOuth of thE YElLoWsTonE to skETch wild aNiMalS.
1844. RObeRt ChaMBers (ScOttisH, 1802–1871) wroTe ThE vesTiges of THe nATuraL HIsTory Of CReAtion (1844) In whICh hE includEd early evOluTIonaRy CoNsideraTions. The most pRiMitive specIeS orIginatED By spontaNeous generation, but these GAve rise To mOre adVancEd ones. ThiS boOk, anonYmoUSly pubLished, Had a pRoFouND EffecT ON WAllAcE. Evolution "WAS thE mannEr In whIch the DIvine Author has been PLeaSed to work".
1845. von SIebOld rECOgNizED PROtoZoA As sINGle-cell
 Nuttall (American?, 1786– 1859) wrot e A M anu alof  the  Orn ithology of th e  Uni ted States and Canada(1832 )t hatw as  to b ecome t h es t and ar dtex to nthe s ubj ect for  most of t he19 th century.18 35. Willia m S wainson (Eng lis h, 178 9– 185 5 ) wro teA Tre atiseo n theGeography  a n d Clas s ificati o n  o f An imals (1835) in w h ic h  he used ad ho c land  b r id g e s t o e xplain ani ma l dis t ributio n s. H e  in c luded some in teresting,s eco nd-han dobs e rvatio ns on  O l d W orld army a nts. 
1836. Wi lliamB uckland (Englis h, 178 4–1 856 ) wr o te  G eol og y  an d  M ine r alo gy Consi de re d wit h Re f e r e ncetonatu ral T heology (1836 ) i n wh i chhe st atedthat  t herewere s evera lcreations.
1839 . Th eodor Sch wan n(Ge rm an, 1 8 10–188 2)wro te  (18 39). Wi t h h im t h ecell theory was ma de g en eral.
18 39. Lo u is  A g assiz (S wi ss- Amer i c an, 1 807– 1 87 3) arriv ed int he  U .S. A f or mer st ud ent  of  Cuvi e r, L ouis A gassiz w as an expert on foss i l fishes. Hef ou n d ed theMus eum of Comp arat i ve Z oolo g y,  at Harva rd Un iv e rs i ty, and became Darw in 's Nor th Am erican opposi tion. He w a s a popula rize r  o f  natural histo ry an d exhorted students  to " study na ture, not b ooks". H is (1 842 –18 4 7 )was a pioneer i n g ef fo rt.
184 0.Jan Eva nge lis taPur ky ně, a Cze ch physi ol og is t,  at  Wroc ł aw propo se s t ha t t he wo r d "pro topla sm"be  a p pli ed to t h ef o rmat iv emate ria lof yo unga nim al embr yos.

184 2.B aron  J us tus von  Liebig wrote  in which h eapp lied c l a ssic met hodology to studying an i mal tis sue s, su gges ted thatani mal he ati s prod uced b y com bu sti o n , and f ou nde dthe scienc e ofbioch em istr y.
1843 . John James Audub o n,age 58, ascen ded  the M is sou r iR ive rt o F o r t Union at themouth of t he Ye llowstonet o s ke tch wil d anima ls.
1 8 44. Rob ert Chamb ers (Scot ti sh,1 8 02– 1871) wrot e the Ve stiges of the N a tu ral H ist ory of  C rea tion(1844) inwhich  he in cl uded e arlyev olutiona ry considerations. Themost p rimit ive  speciesori g ina ted by sp onta neous gene rat ion , but  th e se ga ve r i se  to moreadva n ced ones. Th isb o ok , anonymous l y pub lishe d,h ad a p rofo und effect on Wal l ace. Evolution  "wa s the  ma n nerin  which the Div ine  A u t hor hasbe en pleasedto work" .1 845.von Si eboldrecogni z e dP rotozo a as  si ngle-cell 
 Nuttall_(American?, 1786–1859)_wrote A Manual of_the Ornithology_of_the United_States_and Canada (1832)_that was to_become the standard text_on the subject_for_most of the 19th century.

1835. William Swainson (English, 1789–1855) wrote A Treatise on the_Geography_and Classification_of_Animals_(1835) in which he used_ad hoc land bridges to_explain animal_distributions. He included some interesting, second-hand observations on_Old_World army ants.
1836._William Buckland (English, 1784–1856) wrote Geology and Mineralogy Considered_with Reference to natural Theology (1836)_in which he_stated_that_there were several creations.
1839._Theodor Schwann (German, 1810–1882) wrote _(1839). With him the cell theory_was made general.
1839. Louis Agassiz (Swiss-American, 1807–1873)_arrived in the U.S. A former_student of Cuvier, Louis Agassiz_was an_expert on fossil fishes. He_founded the Museum_of Comparative_Zoology, at Harvard_University, and became Darwin's North American_opposition. He was_a popularizer of natural history and_exhorted_students to "study_nature,_not_books". His_ (1842–1847) was_a_pioneering effort.
1840._Jan_Evangelista Purkyně, a Czech physiologist, at_Wrocław_proposes that the word "protoplasm" be applied_to the formative material_of_young animal embryos.

1842. Baron_Justus von Liebig wrote _in which he applied classic methodology_to studying_animal tissues,_suggested that animal heat is produced by combustion, and founded the_science of biochemistry.
1843. John James Audubon,_age 58, ascended the_Missouri River_to_Fort Union at_the_mouth of_the Yellowstone to sketch wild animals.
1844. Robert_Chambers (Scottish,_1802–1871) wrote the Vestiges of the_Natural History of Creation_(1844)_in which he included early evolutionary_considerations. The most primitive species originated_by spontaneous generation, but these_gave_rise_to more advanced ones. This_book, anonymously published, had a profound_effect on Wallace._Evolution "was the manner in which the_Divine_Author has been pleased to work".
1845._von_Siebold recognized Protozoa as single-cell