:
XIV PLORA OF NEW ZEALAND.
m a n y h u n d re d sp ecimen s o f th e p la n t, g a th e re d iu a ll p a rts o f th e s o u th tem p e r a te h em isp h e re , an d
h av e fo u n d , a fte r a m o s t la b o rio u s com p a riso n , th a t I co u ld n o t d efine it s c h a ra c te rs Avith sufficient
com p reh en siv en e ss from a s tu d y o f its Ncav Z e a lan d p h a se s a lone, n o r u n d e r s ta n d th e la tte r w ith o u t
ex am in in g th o s e o f A u s tra lia , S o u th Afi-ica, a n d S o u th A m e ric a . T h e r e s id e n t m a y fin d tAvo v a rie tie
s o f th is a n d o f m a n y o th e r p la n ts , r e ta in in g th e ir d is tin c tiv e c h a ra c te rs Avithiii h is OAvn ra n g e o f o b se
rv a tio n (for th a t v a rie tie s o fte n do so, an d fo r a v e ry u n c e rta in p e rio d , b o th AA'hen Avild a n d also in
g a rd en s , is n o to rio u s ), a n d h e m a y p e rh a p s h av e to tra v e l fa r b ey o n d h is OAvn is la n d to fin d th e h n k
I haA'e fo u n d , in th e ch a in o f fo rm s th a t u n ite s th e m o s t d is s im ila r s ta te s o f L om a r ía p r o c e r a ; b u t h e
c an n o m o re a rg u e th e n c e fo r th e specific d iffe rence o f th e se , th a n lie c an fo r a specific difference betw
e e n th e a b o rig in a l o f N ew Z e a la n d a n d h im se lf, b e c au se h e m a y n o t fin d in te rm e d ia te fo rms o f h is
ra c e o n th e sp o t. W e do n o t k n ow Avhy v a rie tie s sh o u ld in m a n y cases th u s re ta in th e ir indiAu-
d n a h ty over gi’e a t a re a s, a n d lo se th em in o th e r s ; h u t th e fa c t th a t th e y do so pro v es th a t n o d e d u c tio
n s d raw n from lo c a l o b s e rv a tio n s o n Avidely d is trib u te d p la n ts c an b e co n sid e red conclusive. To
th e am a te u r th e se q u e s tio n s ai’e p e rh ap s o f v e ry triflin g im p o rta n c e , b u t th e y a re o f gi’e a t m om e n t to
th e n a tu r a lis t who re g a rd s a c cu ra te ly -d e fin e d floras as th e m e an s fo r in v e s tig a tin g th e g re a t p h en o m
e n a o f A'egetation; h e h a s to se ek t r u t h am id e rro rs o f o b se rv a tio n a n d ju d gm e n t, an d th e re su ltin g
chaos o f sy n o n ym y AAffiich h a s b e e n a c cum u la ted b y th o u g h tle s s a sp ira n ts to th e q u e s tio n ab le h o n o u i’
o f b e in g th e firs t to n am e a species*.
T h e re a re m a n y cau ses w h ich re n d e r i t ex trem e ly difficnlt to d e te rm in e th e lim its o f species, an d
in some g e n e ra th e o b stac les ap p e a r to in c re a se , th e m o re th e m a te ria ls fo r s tu d y in g th em m u ltip ly ,
an d th e m o re we follow o u r an a ly sis o f th em in to d e t a i l ; h en c e th e b o ta n is t is o fte n le d o n to an
in d e fin ite m u ltip lic a tio n o f species (w ith in c re a sed difficulty o f d e te rm in in g th o s e a lre ad y e s ta b lish ed ),
o r to a re d u c tio n o f a ll to a fcAv, o r to o n e v a riab le species. M y o a a t i im p re ssio n is, th a t th e p ro g re ss
o f b o ta n y p o in ts to th e co n c lu sio n th a t in m a n y g e n e ra we m u s t u ltim a te ly ad o p t m u c h la rg e r \iew s
o f th e v a ria tio n o f species th a n h e re to fo re , a n d th a t th e n um b e r o f supposed k in d s o f p la n ts is (as I
sh a ll in d ic a te elscAvhere) g re a tly o v e r-e s tim a te d ; i f i t b e n o t so, we m u s t e ith e r a dm it th a t species a re
n o t definable, o r th a t th e r e a re h id d e n c h a ra c te rs th ro u g h o u t a ll classes o f th e v eg e tab le k in g d om , o f
Avhich th e b o ta n is t h a s n o cognizance , an d tow a rd s th e a c q u irem e n t o f Avhich, i f th e y a re ev e r to be
rev ea led , a ll efforts in th e d ire c tio n in w h ich we h ave b e e n ad v an c in g ap p e a r to b e vain. Co u ld sy stem
a tis ts as a b o d y b e ac cu sed o f c a rry in g o u t th e ir in v e stig a tio n s in a n u n p h ilo so p h ic a l m a n n e r o r
spii’it, o r w ith o u t d u e a tte n tio n to all th e mo d e s o f te s tin g th e v a lid ity o f ch a ra c te rs, afforded b y th e
s tu d y o f liv in g a n d d rie d p la n ts , b y d ire c t o b se rv a tio n , an d b y ex p e rim en t, th e r e m ig h t be hopes o f
su ch a r e v e la tio n ; b u t su ch h o p es a re in c o n sisten t w ith th e g r e a t ad v an ces th a t h av e h e e n m a d e in
sy stem a tic b o ta n y , which, h a v in g all te n d e d to a m o re p e rfe c t k n ow led g e o f th e affinities o f p la n ts , we
a re a s su red h av e b e e n th e effect o f p ro g re ss in th e r ig h t d ire c tio n .
O f th e g e n e ra to w h ich I h e re allu d e as v ariab le , th e re a re m a n y in N ew Zcalandfi; some o f
* The time however is happily past when it was considered an honour to be the namer of a plant; the botanist
who has the true interests of science at heart, not only feels that the thrusting of an uncalled-for synonym into
the nomenclature of science is an exposure of his own ignorance and deserves censure, but that a wider range
of knowledge and a greater depth of study are required, to prove those dissimilar forms to be identical, which any
superficial observer can separate by words and a name.
f M. Bory de St. Vincent has observed (A’oyagp dans les Quatre principales lies des Mers d’Afrique) with
reference to insular floras, th a t their species are generally variable, an hypothesis scarcely compatible with the fact
that the proportion of species to genera in islands is always small, because the proportion of imported plants, which
is considerable in an island, is made up of species of different genera, having no affinity Avith one another, and
INTRODUCTORY ESSAY.
th e se a rc m u n d a n e , tl ia t is, fo u n d in a ll o r m o s t tem p e ra te o r tro p ic a l c lim a te s as R a n u n c u lu s , Cle-
m a tis, Senecio, a n d m a n y G ra s se s a n d P e r n s ; an d we c a n n o t y e t te ll w h e th e r th e d ifficu lties a re g r ^ e r
w ith th em th a n w ith th e m o re lo c a l o r en d em ic g en e ra , as Coprosma, Celmtsia, Alscmosmia, a n d la -
cophy llum. O f th e m u n d a n e g e n e ra ag a in , some a re chiefly com p o sed o f sp ecies w in ch a re lo c a l (as
is th e case w ith th e th r e e firs t m e n tio n e d ), w h ü e o f o th e rs th e species th em s e lv e s ai-e w id e ly d is tr ibuted,
as those of Poiamoi'eiOT!, iem « « , a n d m a n y F e rn s .
T h e fa c t o f a p la n t h a v in g a wide r a n g e im p lie s its b e in g exposed to c lim a tic diffe ren ces th a
o fte n in d u c e ch an g e , a n d th e co n s eq u en t p ro p a g a tio n o f fo rm s o r ra c e s th a t c a n n o t b e re co g n iz ed as
m em b e rs o f o n e species, w ith o u t fu ll se rie s o f sp e c im en s from m a n y lo c a litie s . I f we allow a suffic
ie n t tim e , i t is q u ite re a so n ab le to su p p o se th a t g eo lo g ic a l o r o th e r n a tu r a l cau ses (p ro d u c in g a
ch a n g e o f clima te) m a y iso la te b y sea o r d e s e rt, o r b y th e in tru s io n o f s tro n g e r p la n ts th a t m o n o p o lize
th e soU, th e o u tly in g a b n o rm a l s ta te s o f a species th a t was o n ce u n ifo rm ly s p re a d o v e r a n area .
T o co n n e c t th o s e d issev e red m em b e rs is o fte n a w o rk o f g r e a t difficulty, fo r in d iv id u a ls o f su ch race s
freq u e n tly r e t a in th e fr c h a ra c te r ev en w h en th e y h av e b e e n u n d e r c u ltiv a tio n fo r m a n y y e a rs .
H y b rid iz a tio n h a s b e e n su p p o sed b y m a n y to h e a n im p o r ta n t e lem e n t in co n fu s in g a n d m a sk u ig
species*. N a tu r e , however, seem s effec tu ally to h av e g u a rd e d a g a in s t it s ex ten s iv e o p e ra tio n a n d its
effects in a n a tu r a l s ta te , a n d as a g e n e ra l ru le th e g e n e ra m o s t ea sily h y b rid iz e d in g a rd e n s , a re n o t
th o s e in wh ich th e species p re s e n t th e g re a te s t difficulties. W i th re g a rd to th e faeiHty w ith w h ich
h y b rid s a re p ro d u c ed , th e p re v a le n t id e as o n th e su b je c t a re e x trem e ly e rro n eo u s . G ä r tn e r , th e
m o s t re c e n t a n d c a re fu l ex p e rim en te r, who ap p e a rs to h a v e p u rs u e d h is in q u frie s in a tr u ly p h ü o so -
p h ic a l sp irit, say s th a t 1 0 ,0 0 0 ex p e rim e n ts u p o n 7 0 0 species p ro d u c ed o n ly 2 5 0 t r u e h y b r id s t- I t
w o u ld h av e h e e n m o s t in te r e s tin g h a d h e ad d e d h ow m a n y o f th e s e p ro d u c ed seeds, a n d h ow m a n y o f
th e la tte r were fe rtile , an d fo r how m a n y g e n e ra tio n s th e y w e re p ro p a g a te d . T h e m o s t s a tisfa c to ry
p ro o f we can ad d u c e, o f h y b rid iz a tio n b e in g p ow erless as a n a g e n t in p ro d u c in g species (however
m u c h i t m ay com b in e th em ), a re th e fa c ts th a t no h y b rid h a s ev e r afforded a c h a ra c te r fo re ig n to th a t
o f its p a re n ts , a n d th a t h y b rid s a re g e n e ra lly c o n s titu tio n a lly w eak , a n d a lm o s t in v a ria b ly b a rre n .
U n is ex u a l J tre e s m u s t offer m a n y fa c ilitie s fo r th e n a tu r a l p ro d u c tio n o f h y b rid s , w h ich , n ev e rth e le ss ,
h av e n ev e r h e e n p roved to o c cu r, n o r a re su ch tr e e s m o re v a ria b le th a n h e rm a p ta o d ite ones.
nothing in common but their fociiity for transportation. From the above-mentioned hypothesis it would hence result
that whilst the differences of one degree (specific) are smali and inconstant, those of a higher degree (generic) are
great and trenchant. To a certain extent, however, these facts are not iiicompatibie, for we can imagine a flora
wiioily composed of a few genera as weil marked (generically) as Coproma and Aheuomia, whose species may yet
be as imdcfinable ; or again, species may be well marked, yet variable in characters which would in no one s opinion
be of specific value.
• Hybridization as an agent in confusing species is a very favourite argument with those who are fond of
founding species on inconstant characters ; wiien shown a specimen combining two such spurious species, tliey at
once pronounce it a hybrid—a very simple way of getting rid of a difficulty. In Ecrns, the most variable of all
plants, hybrids were once generally admitted to exist, but the observations of Snminski have led to the discovery
of their sexual organs, whose arrangement and strncture seem to preclude the possibility of such a phenomenon.
f See his observations on muling, Ilo rt. Soc. Journ. vol. v. and vi. 1850-1851.
I Unisexual plants are very interesting in many points of view, and in none more than in the vaiying development
of the sexes according to circumstances. Oliservations on this subject are veiy much wanted : it has
been stated to depend on local circumstances whether the seeds of a bisexual plant shall come up male or female ;
and the fact of botli kinds of flowers, or even of licrmapln'odite flowers, often occurring on a plant that usually perfects
one sex only (as in the monoecious Ilop-plant described by Mr. Masters in Gavd. Chvoii. 18-17), shows that
we may even speculate on the possibility of dioecious plants having sprung originally from a single parent, whose off