250 have exranded their flov-ers end two others above them not in 



■^lover, of natural size viewed from ^hove, showinr the e:cact gp- 

 pe^TPnce of these plrnts ps the3'' frov in their own locelity. -i^rom 

 this figure it cen eesilj'' he understood from the appearance of the 

 ti''o :^"' ov'er?-.ess frov'th*^ thet the Dlent vjould not easily be detected 

 when out o-^ bloom. ^I. pseudotruncrtelium and 1*^. marmoretun ere 

 sre-"'ish and mottled on the ton somewhat like the mottling often 

 seen on stones, a'^d as they gro^r amonP' prevish stones and pebbles 

 bnried nearly level vlth the ground, are also very difficult to 

 'detect v.'hen out o-f flower. Yet under cultivation in this country 

 it ■'s better not to nl^nt them buried in the soil rs they grov; 

 npturpTiy, because our climate is more humid thrn their own end 

 there is risk o-^ t^.em rotting. 



I have said that these plrnts also form pert, end the greater 

 part, of the very small number (less thr-n 20 I believe) knov/n es 

 'Vindo^-ed (not "/indovO '^Ipnts. T^is is due to their reraprksble 

 stmctur?! r^eculiarities. It is usunl to find that the green col- 

 ours' rr- m^'tter (chlorophyll) of plants forms a layer over the sur- 

 face of lerves and other green parts v;here exposed to light, but 

 in these particular plrnts it does not, for the exposed surface 

 shov s no evidence of being green, i'ig. 112, 1, represents ?■ plant 

 o-f I'. Lesliei ps it grows In the ground, nsturel size. ^^ig. 112, 

 2, is R section? 1 viev^ of the same riant ^ A beinc- the body of the 

 plpnt, comrosed of clear, v.-atery, colourless tissue, through which 

 lif^ht cen easily pass; B is a flower-bud at the bottom of the cen- 

 tral tube through the plant, u^^ w^ich it pushes its vvey to the sur- 

 face; C, G, pre the layers of green chlorophyll, one Ityer cover- 

 ing the sides of the niant end most of it buried under the ground, 

 and tv^o n^rro'- strips of it lininr the mouth of the fissure, all 

 the remainder of the tor> of the plant being quite destitute of 

 ffreen colour ins- matter; but externellj'", where exposed to the light, 

 these layers pre covered with a coloured '"igment that acts as a 

 screen and r>rotects the green chlorophyll from being injured by 

 the intense lirht o-f South ^^fr'ica; ^ is the thin epidermis cover- 

 inc- the ton of the rslent, vrhich in J>i. Lesliei and most of the 

 other species of this grour is mottled or dotted, "^nder this 

 nart o-f the riant the chloronhyll layer is quite absent, and the 

 e^i'^ermis serves exactly the same purpose as a v.dndov; does, all- 

 ovwing light to pass dov/nwerd into the interior under ground por- 

 tion of the Plant and thus reach the chlorophyll layer, 3 being 

 the PTound-level. This wjndo^" is not transparent like clear glass 

 but more nearly resembles semi-trsnsparent glass than anything 

 else, for the whole o-^ the outer v;alis of the cells composing it 

 have imbedded in them minute cr^rstals o"" lime, which act as s 

 screen and modify the intensity of light in the same way that -"ros- 

 ted glass does. There are no crystals in the cells themselves, 

 only in their outer cell V7slls. ^^ portion of this epidermis 

 magni-^ied 130 diameters is represented in 3 (S'ig. 112). The in- 

 tense t'"' of llfTht is also further reduced by the ton or v/lndov 

 beip'^ coloured all over or mottled with a brown, rust-coloured, 

 duT 1 oranP"e, grev or cream.-co"' oured pigment; only in^ i-. opticum 

 and L^, Friedrichi-^e is the window without nigment. i--^. Lesliei is 

 mottled vrith dull orange or rust colour, and it is only v.here 

 these coloured mprkinr:-; occur th' t stoma ta are found on the window 

 part; all the spaces betweem the m^arkinrs are destitute o'" stomata, 

 1"^ i ch Te very minute, and ^ve plentiful on the underground sides 

 of t^e Plant and alonp- the fissure where the choronhyll layer is; 

 t^'o of them represented in ^irr. 11'^. some distance from the margin. 



