VAXILLA 



VANlLLA (Sp:uiisli, littl,: !<lu',ilh or/i'UM. Onlii,l,},;;r. 

 Vanilla. C'limbiug-oivliiaswliiisi' hrauched sti'ins nscriid 

 to a height of many tret. The nodes hear leaves orseales 

 and aerial roots in alternate arranu'enn-nt. FIs. in axil- 

 lary raeemes or .sjiikes. withont an involnore at the io|i 

 o£ the ovary; sepals and petals siniihir. siin-adiii^-; la- 

 helluni nnitedwith tlie <'olun'.n, the linih eTiveldpini;- the 

 upper portion of the latter; eolunin not winded. Ah(.iit 

 20 speeies in the tro|M<'s. 



The most important s[ieeii;s is I', i^hnnfoj :<f . 11m- \'a- 

 uilUi of ci>niuier(M'. U is ;i nati\ o of 3lexieo. hnl ism.w- 

 widely eultivated in tin' West Indies. . I a\-:i . Iloutl'on, 

 Jlauritins and otlni- inlands nf tho tropiis. iis ,-hir[ 

 requirement hein?;' a hot, damp .diniate. The )i|;iiHs are 

 propagated by cuttings varying in length from 2 to 

 about r2 ft., the longer ones being the nmre satisfae- 

 tory. These ore either planted in tln> ground or m.n'ely 

 tied to a tree so that tln-y are not in direct cnnu'etioii 

 with the earth. TIm'\- somu send our aerial ronts. by 

 which ci)nnecrion with the soil is established. They are 

 u.sually trained i'M trees sn Tied the steins are supjiorted 

 by the forlsed tiranchcs, but posts and trellises are also 

 used as supports. In most pla.'es whore Vanilla culture 

 is carried on pollinatint;' insei-ts are laci<ing and the 

 flowers must be pollinated b\" band. Plants luar their 

 first fruit about three years after setting. They then 

 continue to fruit for oii or 40 years, bearing up to 50 

 pod.s annually. Tlie Vanilla p..ds are picked before 

 they are ripe, and dried. The vanillin crystalHzes on 

 the outside. For a full description of Vaidlla cul- 

 ture and methods of curing the yiods, see liull. No. 

 21, r. y. Dept. of Agriculture, Div. of Botany, by 8. J. 

 Galhraitb. Vanillin is also made from other sources 

 by chemical meaits. The genus was nronoi,a'a)ibed in 

 1S9G by R. A. RoUe in .Jouru. Linn. Soc, vol. 22. 



planiSdlia, Andrews ( r. cirrnnr'ifir-a, Willd. in part). 

 Fig. 20:>0. Common Vanilla. Vanilla Be.vn (fnuu 

 the pods). Tall climbing herbs with stout stems: 

 Its. thick, oblong- lanceolate, acuminate, with short, 

 stout petioles: tls. yellow, large, in axillary racemes of 

 20 or more blossoms; sepals and petals oblanceolate; 

 labellum trumpet-shaped, with small, reflexed, crenulate 

 lobes. "Winter. A native of JMexico Init widely cultivated 

 throughout the trrducs and in greenhouses. B.I\1. 71'>7. 

 L.B. 0.8:733. G.C. III. 2.3:2i:j: Gn. ;57, p. 3.3. 



aromatica, Sw. Stem ane-nbir: Ivs. broadly ovate, 

 with a Ijluntish peint, eontraeted at the base: tls. green- 

 ish and white. .J:tmai'-a, Colombi:(. Trinid:id. 



Heinkich Ha.sseleking. 



VARIEtlATKiN 



1901 



VANILLA PLANT. 



V,i),ill,i. above. 



Tr 



uh.nifi.s 



VAEIEGATION. This term is usually ap|ilie.l to a 

 classof variations, especially in leaf coloratii.uj, in which 

 the leaves become striped. bande<l, spotted, blotched, 

 etc., with yellow, white, red ami various other celors in 

 connection with the normal green of other porticms of 

 the leaves. In the case of yello\Y and white variegation, 

 the term albinism is sometimes used. espe<-i.ally when 

 the plants are largely marked with white <u' yellow, as 

 in ^ibnttIon SeUoiria nnm . P^hi n/"it i inn i<ntii!r, ami va- 

 riegated forms of _Ennni/i)' Its Jti/'iniirits, Jlijdiil tuji a 

 liortensis, Sedera Hells. Pmm.r \''rlnrhv and others. 



Among the dracti^nas, caladiums and codiai-ums, be- 

 sides the white variee-.ation, there are developed beauti- 

 ful reds, pinks, yelhov, etc. As a rule, the term varie- 

 gation is not used in cases of color variation in wdii'dj 

 only the surface of the bcif is im-olved, as in many of 

 the begonias, sansevierias [S. frui t/rrusis ami S.Zrtj- 

 hiiii,;n. Alornsi,!. ,-„/,n',i, Cissii.s r//,sc„^,c. and others. 

 Fig. 2041. In many su(di plants the m.arkings ;iie due 

 in part to hairs, scales, or air in the ruiticle or I'pider- 

 mal cells, as in Sansevieria and Begonia. In some hc- 

 gonias. many varieties of C'alathea (as C. oyiitila. y-av. 

 alhn-li),r,ifa], etc., the epidermal cells develop decided 

 and delinite color v;iriation, though the changes do not 

 usually involve the mesophyll or inner cells of the leaf. 

 In some genera, however, especially Calathea, wa- liud 

 all gradations between purely epi<lermal variegation and 

 changes involving the deeper l;iyers of tlie leaf, as in 

 C. I'eili-llii and C. jrnkoiiinio . The sann; is true of 



man>- other genera,. Differeid kinds of variegation are 

 shown in I'igs. 20 10-1. 



'irue variegations nuiy lie distinguished from ordinary 

 cohir:dions, bleachini;-. chhu'osis. etc., by ihi' f:ict that 



tl loi'ed ai'eas ate usuallv (piit.' sliarjilv d. dined. 



They d.. not grailually blend int.. .'a.di ..tli.a\' but h;iv6 

 d. linit.' bonmlari.-s. Cells in lb.- \-ari..gat .■.! ari-as are 

 f..un.l, as a ml.', t.. .-..ntain th.' s:.nie i-ld..ro|.b vll bodies 

 (idicmatophoivs) :is Ih.. or.linatv green (adis ..f the 

 l.lant. H..wev..r. in III.- varh-gati-il'iiarts, tin- green .•.dor 



is net .l..v,do|..-.l, :ind tl Ii toinat..pli..r.-s an- ..ffen 



siiKilb-r .ir are somewhat swelle.l and vacuohit... In the 





2640. Varieg^at 



n Abutilon. 



case of chlorosis, due to the hick of iron, or yellowing 

 due to the lack of liy,-ht, a leaf will quickly develop its 

 normal color if .ariven the proper conditions. This is 

 not the case, however, in v:(ri(_-y:ated leaves. While the 

 intt-nsity of whatever L-olor tlie chromatophores may 

 have can be varied hy li^ht and food, a variegated cell 

 CLin never be changed l>y these means to a normal ceU. 



The chlorophyll granules (chromatophores) appear to 

 liavi.^ lost entirely, in many cases, the power to make 

 stai'clj and sugar from the carbonic acid gas in the air, 

 ami in ntlier cases this power is very greatly reduced. 

 Ill I'racrically all cases, however, wlien the cliromato- 

 piiMi-cs are not destroyed, they retain the power to ron- 

 VL'i-t sUL;av into srarcb and tli^y tbus store u]i starrli in 

 tiieir tissues fnnn tlie sugar ujanufactnred bv tlie 

 h(*;i.lthy cells of tin- lcat\ 



Wliiie or albino variegation is of course due to a lark 

 of any i^oloring in the chromatophores, and some- 

 times to tlio entire alisence of these bodies. The ,-ells 

 sei'iii to have Inst CMinpletely tlie power of making 

 rblorophyll. T]i<'>.e a]l)i<;ant vai'icgations are to be 

 h"ik,>,l uiion as the more extreme forms of variegatiiin, 

 an<l usually arise tbi-oi]^-)i a feelile or atrophied condi- 

 tion nf the plant. Seedlings raised from parents both 

 of which are variegated in this way are usually vei'v 

 weak. High feeding and favorable conditions of 

 growth, while tbe\- will jmt cause a variegated plant to 

 return to its normal rundition. will often stimulate the 

 <levelopment of a normal green shoot that takes uust 

 of tlie nourishment and tVius causes the starvation and 

 <lisaiipearance of the albicant parts. In other cases, as 

 in codirennis, niodilied I'liloi-ophy]) is niarle. T^ari^'e }"(d- 

 h'wish oil - like drops occur in the substance vi the 



