THE LEAVES. 23 



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

 nata), when the bases of two opposite leaves join around the stem (Honeysuckle, fig. 67, 

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

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

 (f. altei*na; Stock, fig. 1; Toad-flax, fig. 2 ; Oak, fig. 5) ; opposite (f. opposita, St. 

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

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

 right and left (Yew, 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 

 (f. glauca) when of a whitish dusty green or blue (Poppy, Cabbage) ; spotted (f. 

 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 Ama.ranth) ; 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 (f. plana), when their blade is much flattened, as is usually 

 the case (Lime, fig. 86) ; cylindric or terete (f. 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 (f. ovata), 

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

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

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

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

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

 spathulate (/. spathulata), when the blade is narrow at the base, and large and 

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

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

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

 fig. 77). 



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

 and diminishes insensibly towards the extremities (Privet, fig. 78) ; linear (f. 

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

 them narrow (Toad-flax, fig. 2) ; ensiform (f. 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 (f. acerosa), when the 

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



