in botany, and led to almost universal dissatisfaction with the old method of ...
illustrate function, process, and relationship throughout the wide range of plant
life ...
PREFACE
.
TH E
pre s e nt b ook is t he r es u l t of a re vi s ion an d e l a bor a tio n ” O f t he a uthor s E l e m e nt a ry B ot a ny Th e Ne w Y ork 1 8 9 8 g e n e r a l p l a n of the p a rt s o n phy s io l o g y a n d g e n e r al m orpho l o g y r e m a in s un c h a n g e d A nu mb e r of th e ch a pt e rs i n the phy s i o l o g i c a l p a rt a re pra ctic all y u ntou c h e d whi l e oth e rs a re th orou g h l y r e vi se d a n d c onsi d e r a b l e n e w m a tt e r is a dde d e s p e ci a ll y on t he s ubj e ct s of nutrition a n d d i g e s tion Th e pri ncip a l ch a pt e rs o n g e n e r al morpho l o g y a re u n c h a n g e d or on l y s l i g h t l y m o d ifi e d t h e g r e a t e s t ch a n e b e in g g i n a r e vi s ion of t h e s ubj e c t of t h e m orpho l o g y of fe rti l iz a tion i n th e g ym no s p e rm s an d a n g i o sp e rm s i n or d e r to bri n g thi s subj e c t a b re a s t of the d i sc ov e ri e s of t h e p a s t fe w y e a r s O n e of th e g r e a t e s t mo d i fi c a tion s h as b e e n i n t h e a d di ti on of ch a pt e r s on t h e c l a ssi fic a ti on of t h e a l ae a n d g f u n g i with s tu di e s of a dd i tion a l e x a mp l e s for t he b e n e fit of th o se s ch oo l s wh e r e t h e tim e a ll o w e d for t h e fir s t y e a r s cou r se m a k e s d e s i r a b l e t he e x a mi n a tion of a bro a d e r r a n g e of re pr e se nt a tiv e p l a nt s The c la ssi fi c a tion is al s o c a rr i e d out with g r e a t e r d e fi n it e ne ss so th a t the re g u la r se qu e nc e of c l a sse s or d e r s a n d f a mi l i e s is g i v e n a t t he c l o se of e a c h of t he s ubki n g d om s Th u s a ll the c la sse s a ll t he or d e r s (e x ce pt a fe w i n the al g a ) an d m a ny of t he f a mi l i e s a re g iv e n f or t h e a l g ae f u n g i mo sse s l i v e rwort s pt e ri d ophyt e s g ym no s p e rm s a n d a n g io s p e rm s B u t by fa r t he g r e at es t i mprov e m e nt ha s b e e n i n the c om p l e t e re org a niz a tio n r e writi n g a n d e l a bor a ti on of th e p a rt d e a l i n g with e co l o g y whi ch ha s b e e n m a d e po ss ib l e by s t u d i e s of t he p a s t fe w y e a rs so th a t t he s ubj e c t c a n b e pr e se nt e d i n a m or e l og ic al an d coh e r e nt f or m A s a r es u l t th e s ubj e c t -m a tt e r o f “
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iii
PRE FA CE
IV
the b ook
.
fa ll s
n a tu r a ll y i nto thr e e p a rts whi c h m a y b e p a sse d i n r e vi e w a s fo ll ow s : Pa rt I Ph ys i ol og y Thi s d e a l s wi th the l i fe pro c e sses of p l a n t s a s a b s orption tr a n s pir a tion c on d u c tion ph oto s ynth e s i s nut ri tion d i g e s tion r es pi r a tion g rowth a n d i rri t a bi li ty a ss imi l a ti o n S i n c e pr o top l a s m is fu n d a m e nt a l to a l l t he l i fe work of t he p l a nt thi s s ubj e c t i s d e a l t wit h fir s t a n d t he s t u d e nt is le d throu g h t he s tu d y of a n d e xp e rim e nt a tion wi th th e s imp l e r a s w e ll a s s om e of the h i g h e r p l a nt s to a g e n e r a l un d e r s t a n d in g of protop l a s m a n d t h e s p e c i a l wa y i n whi c h i t e n a b l e s t h e p l a nt to c a rry on i ts work a n d to a d j u s t i t se l f t o th e c on d i tion s of it s e xi s t e n c e Thi s s tu d y a l s o se rv es th e purpo se of fa mi l i a rizi ng th e pupi l wi th s om e of t h e l o w e r a n d u n f a mi l i a r p l a nt s S om e t e a c h e rs wi ll pre fe r t o b e g i n th e s tu d y with g e n e ra l morph o l og y a n d c l a ss i fi c a tion thu s s tu d yin g fir s t t he r e pre se m t a t iv e s o f t h e g r e a t g roup s o f p l a nt s a n d oth e r s wi ll pr e fe r t o d we ll firs t on t h e e c o l o g i c a l a s p e c t s of v e g e t a ti on Thi s c a n b e d on e i n t he u s e of thi s book by b e g i nni n g with Pa rt I I or with Pa rt II I B u t the a u thor b e l i e v e s th a t m orph o l o g y c a n b e s t b e com pre h e nd e d a ft e r a g e n e r a l s tu d y of l i fe pro ce s se s a n d fu n c tion s of t he d i ff e r e nt p a rt s of p l a nt s i nc l u d in g i n thi s s tu d y s om e of t he l ow e r f orm s of p l a nt l i fe wh e r e s om e o f th e s e proc e sse s c a n more re a d i l y b e ob s e rv e d The pupi l is th e n pr e p a re d for a mor e i nt e ll i g e nt c on s i d e r a tion of g e n e r al a n d comp a ra ti v e E v e n mor e i mport a nt i s a fi rs t morpho l og y a n d r e l a tion s hip s s tu d y of phy s io l o g y b e f or e t a kin g up t he s ubj e c t of e co l o y g Th e g r e a t v a l u e to b e d e ri v e d f rom a s t u d y of p l a nts i n th e i r r e l a ti o n to e nviro nm e nt l i e s i n th e a bi l ity to i nt e rpr e t the d if f e re n t s t a t e s c on d ition s b e h a vior a n d a ss o c i a tion s o f the p la nt a n d for thi s phy s i o l o g y is i n d i s p e n s a b l e I t is tru e th a t a con s id e ra b l e m e a s ur e of s u c ce ss c a n b e ob t a i n e d by a g oo d t e a ch e r i n b e g i nnin g w i th e ith e r s ubj e c t but t he w rit e r b e li e v e s th a t m e as u re o f s u c c e ss wou l d b e g re a t e r i f th e s ubj e c t s w e r e t ake n u p i n t h e or d e r pr e se nt e d h e r e Pa rt I I Morp hol og y a n d l ife h is tory of repre sen ta t i v e pl a nt s ,
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P R E FA CE
V
.
Thi s i nc l u de s a r a th e r c a re f u l s tu d y of r e pr e s e nt a ti ve e x a mp l e s a m on g t h e a l g ae f u n g i li v e rwort s mo ss e s f e rn s a n d th e i r al l i e s g ym no sp e rm s a n d a n g io s p e rm s w i th e sp e ci a l e mph a si s on t h e f orm of p l a nt p a rt s a n d a c omp a ri s on of th e m i n t he d i ff e r e nt g roup s wi th a c omp a r a tiv e s tu d y of d e v e l opm e nt r e pro d u c tion a n d fe rti li z a ti on roun d in g ou t th e w ork wi th a s tu d y of l i f e hi s tori e s a n d n o ti n g p ro g r e ss ion a n d r e tr o r ess ion g o f c e rt a i n or a n s a n d ph a se s i n pro ce e d i n g g f rom t h e l ow e r t o t h e hi g h e r p l an t s Thu s i n th e a l g ze a fir s t c ri ti c a l s tu d y is m a d e of f ou r e x a mp l es w hi c h i ll u s tr a t e i n a m a rk e d w a y p ro g r e s s i v e s t a g e s o f t h e p l a nt bo d y se xu a l or g a n s a n d r e pr o d u c tion Ad d i t i on a l e x a m p l e s a re th e n s tu d i e d f or t he pu rpo se of a c qui ri n g a k no w l e d g e of v a ri a tion s f rom th ese t v p e s a n d t o g iv e a bro a d e r b a s i s for th e b ri e f c on s i d e r a ti on of g e n e r a l r e l a tion s hip s a n d c l a ss i fi c a tion A s imi l a r p l a n i s f o ll o w e d i n t h e o th e r g r e a t g roup s T he pro c e sse s of f e rti li z a tion a n d r e pro d u c ti o n c a n b e m o s t e a silv ob se rv e d i n t h e l o w e r p l a nt s li k e t h e a l g a a n d fun g i a n d thi s i s a n a dd i tio n a l a r g um e nt i n f a vor of g i vi n g e mph a s i s to th ese f orm s of p l a nt l i fe a s w e ll a s t h e a d v a nt a g e o f pro ce e d i n g l o g i c H a vi n g a l s o l e a rn e d a ll y f rom s i mp l e r to mor e c o m p l e x f orm s s om e of th e se p l a nt s i n ou r s t u d y of phy s io l o g y we a re fo ll o w i n g r e co g niz e d ru l e of p e d a g o g y i e pro c e e d i n g f rom a noth e r k now n obj e ct s to u nk no w n s tru c tur e s a n d proc e sse s Th rou g h t h e s tu d y of t h e or g a n s of r e pro d u c tion of t h e l o w e r p l a nt s a n d b y g e n e r a l comp a r a ti v e morpho l o g y we h a v e c om e to a n u n d e r a n d of s t a n di n g oi t h e mo rpho l o g y of t h e p a rt s of t h e flo we r t he t ru e s e xu a l org a n s of t h e s e e d p l a nt s a n d n o s tu d e nt c a n hop e to prop e r l y i nt e rpr e t t he s i g ni fi c a n ce of t h e flo w e r or t h e s e xu a l or g a n s of t h e s e e d p l a nt s w h o n e g l e c t s a c a r e f u l s tu d y o f t h e g e n e r a l m orpho l o g y o f t h e l ow e r p l a nt s Thi s p a rt Pa rt I I I Pl a n t me mbers i n rel a ti on to e n v i ron men t d e a l s wi th th e or g an iz a ti on of t he p l a n t bo d y a s a wh o l e i n i ts r e l a tion t o e nvi ronm e nt t h e org a niz a tion of p l a nt ti ssu e s wi th a d i s c u ss ion of t h e pri n c i p a l ti ss u e s a n d a d e s c ripti v e s ynop s i s of T h is i s f o ll o w e d by a c o mp l e t e s tu d y f rom a bi o l o g i c a l the sa m e ,
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vi
P RE FA CE
.
t nd point of th e d i ff e re nt m e mb e rs of t he p l a nt th e ir sp e c i a l Th e s t e m fu n c tion a n d th e ir s p e c i a l r e l a ti on s to e nvi ronm e nt root l e a f fl o w e r e t c a re c a r e f u ll y e x a mi n e d a n d th e i r e co l og i c a l re l a tion s poi nt e d out Thi s tog e th e r wi th th e s tu d y of phy s io l o g y a n d r e pr e se nt a ti v es i n t h e g roup s of p l a nt s f orm s a th orou g h b a si s for pur e p l a nt e c o l og y or t he s p e ci a l s tu d y of v eg e t a ti o n i n i t s r e l a tion to e nvironm e nt Th e re i s a s tu d y of t h e fa c tor s of e nvi ro nm e nt or e c o l o g i c a l fa c tor s whi c h i n g e n e r a l a re g r o up e d u n d e r t h e ph y s i c a l c l i m a ti c Thi s i s f o ll ow e d by a n a n a l y s i s of v e g e t a a n d bi oti c f a c tor s tion fo rm s a n d s tru c tur es p l a nt form a tion s a n d s o c i e ti e s Th e n i n or d e r a re tr e a t e d bri e fly f or e s t s o c i e ti e s p ra iri e s o c i e ti e s d e s e rt s o c i e ti e s a r c ti c a n d a l pin e s o c i e ti es a qu a ti c s o c i e ti e s a n d t h e s p e c i a l s o c i e ti e s of s a n d y ro c ky a n d m a r shy p l a c e s A c kn ow l edg me n ts Th e a uthor wi s h e s to e xpr e ss his g r a t e f u l n ess t o a ll tho s e wh o h a v e g i v e n a id i n th e pr e p a r a ti on o f thi s w ork or of t h e e a r l i e r e d ition s o f E l e m e nt a ry B ot a ny ; to hi s a ss o c i a t e s D r E J D ur a n d D r K M W i e g a n d an d Pro fe ss or W W Ro w l e e of t he b o t a ni c a l d e p a rtm e nt a n d to Pro fe s s or B M D u g g a r o f t h e U niv e r s ity o f M i sso uri Pro fe s s or J C A rthu r of Pu r d u e U ni v e r s i ty a n d Pro fe ss or W F G a non g of S mith Co ll e g e f or r e a d in g on e or mor e porti on s o f t h e t e xt ; a s w e l l a s t o a ll th o se w h o h a v e c ontribut e d i ll u s tr a ti on s I ll u s tra ti on s Th e l a r g e m a j ori ty of th e i ll u s tra tion s a re n e w (or a re t h e s a m e a s tho se u s e d i n e a r l i e r e d i tion s of t he a u th or s E l e m e nt a ry B ot a ny ) a n d w e r e m a d e wi th s p e c i a l r e f e r e n c e to t h e m e tho d o f tr e a tm e nt fo ll o w e d i n t h e t e xt M a n y of th e ph ot og r a ph s w e r e m a d e by t he a uthor O th e rs w e r e c o ntribu t e d by Pr o fe ss or Ro w l e e of Corn e ll U ni v e rs i ty ; M r J oh n G i ff o r d of N e w J e r se y ; Pro fe ss or B M D u g g a r U niv e r s i ty of M i s s o uri ; Pr o fe ss o r C E B e s s e y U n i v e rs ity o f N e b r a s k a ; D r M B H ow e N e w Y o rk B ot a ni c a l G a r d e n ; M r G i fford Pi n c h o t Chi e f o f M r B T G a ll ow a y Chi e f o f th e t he B ur e a u o f Fo r e s t ry ; B u r e a u o f Pl a nt I n d u s try ; Pr o fe s so r T u o m e y o f Y a l e U ni v e r s i ty ; E H H a rri m a n w h o t h r o u g h D r C H M e rri a m an d M r of t he Nati o n a l M us eu m a ll o we d t he us e o f se v e r a l o f his c opy
s a
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P R E FA CE
h t e d photo gra ph s f rom A l a s k a To tho se who h ave con t ri bu t e d d r a wi n g s t h e a u thor i s i n d e bt e d a s f o ll ow s : to Pro fe ss or M a r g a r e t C Fe rg u s on W e ll e s l e y Co ll e g e ; Profe ssor B e rth a S t on e m a n of H u g u e not Co ll e g e S outh Afri ca ; Mr H H a sse l bri n g of Chi ca g o ; D r K M iy a k e f orm e r l y of Corn e ll U ni v e r si ty a n d now of D os hi sh a Co ll e g e Ja p a n ; a n d Prof e ss or s I k e no Th e a uth or and H ir a se of t he Toki o I mp e ri a l U niv e r s i ty B o s ton for t h e privi l e g e to Co i s a l s o i n d e bt e d to G i nn ” Fi r s t S tu d i es of Pl a nt L i fe th e f o ll o wi n g fi g ur e s : u se f rom h is
ri g
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28,
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4 6 , 48 , 4 9 , 5 6, 6 2 , 66 , 6 7 , 8 7 ,
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1 03 ,
— 2 2 0 8 8 47 5 44 , 44 3 , 444 , 4 4 , 44 9 , 4 5 , 4 7 43 a c k now l e d g e d i n t h e t e xt
CO RN E LL U NI VE RS I TY, A p ri l ,
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— 26 2 2 4 4 ,
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TABLE O F CO NTENTS
CHA PTE R 1
CH APTE R I I A B S O RPTI O N , DI FFU S I O N , O s sros rz
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tu d y o f p l a n t l i fe a n d g ro w th i t wi l l b e f oun d c o nv e ni e n t firs t to i nqui re i nt o t h e n a tur e o f t he s ub st a n c e w h i c h w e c a l l t he l i vi n g m a t e ri a l o f p l a nt s For p l a n t g ro w th a s w e l l a s s om e o f t h e o th e r p ro c e ss e s of p l a n t l i fe a re a t bo ttom Thi s l iv i n g m a t t e r is c al l e d i n d e p e n d e nt o n t hi s l i vi n g m a tt e r g e n e ra l p r otop l a s m 2 I n m o s t c a ses p ro top l as m c a nno t b e se e n wi th out t he h e l p o f a m i c ro sc op e a n d i t wi l l b e n e c e ssa ry for u s h e r e t o e m p l oy on e if we w i s h t o se e protop l as m a n d t o s a ti sf y ourse l v e s b y e x a m i n a t i o n th a t t he s ub s t a n c e we a re d e a l i n g w ith is p ro t op l as m 3 We s h al l fi n d i t c onve ni e n t firs t t o e x a mi n e prot op l as m i n s om e o f t h e s i mp l e r p l a n t s ; p l a n t s w hi c h f rom th e i r mi nut e s i z e a n d s i mp l e s tru c tur e a r e so t ra n s p a r e nt th a t w h e n e x a mi n e d w i th t h e m i c ro sc op e t h e i nt e ri or c a n b e s e e n For our fi rs t s tu d y l e t us ta k e a p l a nt k nown a s sp z r ogy r a thou g h th e r e a re a numb e r o f oth e rs w h i c h wo u l d se rv e t h e p u r po se qui t e a s we l l a n d m a y qui t e as e as i l y b e O bt a i n e d for s tu d y 1
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