Til] HAIRINESS, ETC. 37 



in Laburnum and White Willow ; pilose or velvety and 

 almost woolly as in Apple ; tomentose or densely woolly 

 or cottony as in Cotoneaster, White Poplar, Pyrus Aria, &c. ; 

 hispid when covered with stiff bristly hairs as in many 

 Boragineae, or scabrid when the stiff hairs are shorter, 

 giving a harsh feel, reminding one of a file, as in the 

 Wych Elm and Fig. 



In some cases the hairs are glandular, and secrete 

 viscid substances, as in the Hazel ; in others they are 

 more or less stellate as in the Plane and Viburnum Lan- 

 tana ; or they are peltate and scale-like, giving the leaf a 

 peculiar glistening scurfy appearance, often silvery or 

 bronzed, as in Hippophae and Eleagnus. 



Hairs fringing the margins render the latter ciliate, as 

 in the Beech, where the young leaves are ciliate with silky 

 hairs : in the Barberry the slender teeth similarly render 

 the margins ciliate -dentate, while in the Holly the margin 

 is spinose, owing to the outstanding prickly teeth. 



The ordinary thin green leaf is membranous or herb- 

 aceous, as in the Plane, Norway Maple, Dogwood, &c.; 

 or it may be thicker and soft, or fleshy, as in many 

 Crassulacese, Sedum, &c., passing to a more leathery 

 texture, as in Mistletoe, Holly, Pines, Firs, &c., when it 

 is termed coriaceous. 



Leaves marked with spots or blotches of different 

 colours are maculate or variegated, as in the Arum, Orchids, 

 Aucuba and many cultivated forms of Holly, Ivy, Maples, 

 &c. These cases must be distinguished from blotching 

 and spotting due to disease-fungi and other pathological 

 conditions. In some cases the leaves have purple or red 

 under-surfaces as in some Sycamores ; or the whole leaf 

 assumes such colours, as in ,the Copper Beech. Here 

 again we must carefully distinguish between the dis- 

 colorations or bright hues of normal leaves, and those 

 due to the moribund tissues of autumn leaves. 



