THE LEAVES. 23 



the stem is then winged [caulis alatus, Comfrey, fig. 66) ; — confluent or connate (/. con- 

 nata), -when the bases of two opposite leaves join around the stem {HoneysucMe, fig. 67, 

 Ghlora) ; — when the base of a single leaf spreads completely round the stem, the stem 

 and leaves are perfoliate (c. /. perfoliatus, Bupleurum, fig. 68) . Leaves are alternate 

 (/. alterna. Stock, fig. 1; Toad-flax, fig. 2 ; Oak, fig. 5) inapposite (/. opposita, St. 

 John''s Wort, fig. 3) ; — whorled (/. verticillata. Oleander, fig. 82 ; Madder, fig. 4) ; — 

 distichous (/. disticha), when they spring from alternate nodes placed on two lines to 

 right and left {Tew, fig. 69) ;— fascicled (f. fasciculata), when crowded into a bundle 

 on very short branches {Weymouth Pine, fig. 70). In true Pines this bundle is 

 persistent ; in larches the leaves become solitary and scattered, in consequence of 

 the elongation of the axis. Imbricated leaves (/. imbricata) overlap like roof-tiles 

 {Houseleek, Cypress, Thuja). 



Colour of Leaves. — Leaves are green when of the usual colour; — glaucous 

 (/. glauca) when of a whitish dust}'' green or blue {Poppy, Cabbage) ; — spotted (/. 

 maculata) when they have spots of a different colour from the ground {Arum) ; — 

 variegated {f. variegata) when they are of many colours arranged without order 

 {variegated Holly, tricoloured Amaranth) ; — hoary {f. incana), when they owe their 

 colour to short and close hairs {Ten-week-stock). 



Forms of Leaves. — Without being precisely alike, yet the leaves of any one plant 

 are usually very similar ; but in some species they are obviously dissimilar {Paper 

 Mulberry, Calthrop, Water Crowfoot, fig. 71 ; Shepherd's purse, fig. 72) ; the plant is 

 then said to be heterophyllous {pi. heterophylla). 



Leaves are plane (/. plana), when their blade is much flattened, as is usually 

 the case {Lime, fig. 86) ; — cylindric or terete (/. teretia), when the blade is rounded 

 throughout its length {Sedum, fig. 73); — orbicular {f.orbiculata), when the circum- 

 ference of the blade is more or less circular {small Mallow, fig. 74) ; — ovate (/. ovata), 

 when the blade resembles the longitudinal section of an egg, with the larger end at 

 the base {Pear, fig. 75) ; — obovate (/. obovata), when ovate, with the smaller end at 

 the base {Meadow-sweet, St. John's Wort) ; — oblong (/. oblonga), when the width is 

 about a third of the length {small Centaury) ; — elliptic (/. elliptica), when the two 

 ends of the blade are rounded and equal, like an ellipse {St. John's Wort, fig. 3) ; — 

 spathulate {f. spathulata), when the blade is narrow at the base, and large and 

 rounded at the end, like a spatula {Easter Daisy, fig. 76) ; — angular (/. angulata), 

 when the circumference of the leaf presents three or more angles ; — deltoid (/. 

 deltoidea), if it presents three nearly equal angles, like a delta, A {Chenopodium, 

 fig. 77). 



Leaves are lanceolate (/. lanceolata), when the blade is largest in the middle, 

 and diminishes insensibly towards the extremities {Privet, fig. 78) ; — linear (/. 

 linearia), when the sides of the blade are nearly parallel, and the space between 

 them narrow {Toad-flax, fig. 2); — ensiform (/. ensiformia) , when of the shape of a 

 sword ; in this case, the two surfaces are in apposition and consolidated in the upper 

 part {Iris, fig. 79) ; — subulate \f. subulata), when the cylindrical blade terminates 

 somewhat like an awl {Ledum reflexum) ; — needle-shaped (/. acerosa), when the 

 blade is hard, narrow, and pointed like a needle {Pine, fig. 70, Juniper, fig. 80) ; — ■ 



