126 PUBESCENCE, ETC. [CH. 



rusty hairs of the shoots of Pinus Cembra, twigs of Cydonia, 

 and buds of Wych Elm, and the dark hairs on the fruit of 

 the Gorse, and the shoots of the Gooseberry. 



When the hairs are short, soft and downy, owing to 

 their close crowding, the surface is said to be pubescent 

 as a general term or velvety, when the little soft 

 hairs stand up close and dense like the short pile of 

 velvet. Pilose is the term applied when the velvety pile 

 is softer and longer (Fig. 52 6) ; puberulent when it is so 

 slight that the short-piled down is hardly, but just per- 

 ceptible. Examples are furnished by the puberulous 

 twigs of some Birches, and Chestnut, and the buds of 

 Prunus Padus and other species of Prunus; the pubes- 

 cent twigs of Acer campestre, Hornbeam, shoots of 

 Blackthorn and Prunus insititia, Quercus Cerris and Q. 

 pubescens, and the buds and shoots of Rhamnus Frangula\ 

 the velvety pubescent twigs of Apple, Cotoneaster and 

 Salix viminalis, and the buds of Cornus sanguined', the 

 velvety pilose shoots of Gorse and Salix nigricans] or the 

 pilose shoots of Rhus typhina, &c. 



When the hairs are looser and longer, and more cottony 

 or woolly to the feel (Fig. 52 a and e), the peculiar soft 

 hairiness is termed tomentose or cottony, as on the buds 

 and twigs of the White Poplar ; but when the pubescence 

 consists of straight hairs, flattened on the surface of the 

 epidermis (Fig. 52 c), and glistening white, the appearance 

 is aptly described as silky e.g. the shoots of Laburnum 

 and the twigs of the White Willow. Similarly silky 

 hairs standing out from the margins of buds and leaves, 

 and fringing them, are termed cilia : the young leaves 

 and bud-scales of the Beech afford a good example 

 (Fig. 26 df), as do also the bud-scales of Elms, Rowan, 

 Pyrus Aria, &c. 



The peculiar greyish meally appearance of the shoots 



