26 



OEGAJSrOGEAPHY AND GLOSSOLOGY. 



Hairs and Spines on the Margins of Leaves. — The leaf is ciliate (/. ciliatum), when 

 its margins bear long hairs like eyelashes (Sundew, fig. 92) ; — spinous {/. spinosum), 

 when the nerves lengthen and harden into thorns [Holly, fig. 93 ; Barberry, 

 fig. 94) ; in Berheris, the leaves which first appear after germination are provided 

 r with parenchyma like ordinary leaves, and the base 



,'fl// of their petiole is furnished with two little stipules ; 



but on the subsequent branches the stipules harden, 

 lengthen into spines, and the leaf itself is reduced to one 



94. Barberry. Spiny leaves. 92. Sundew. Ciliate leaf. 9S. Holly. Spiny leaf. 95. Gooseberry. Spines. 



or three thickened and spinous nerves, from the axils of which short branches, 

 bearing ordinary leaves, are developed. In the Gooseberry (fig. 95) the three or 

 five spines (c) which spring below the leaves (f) may be con- 

 sidered as a development of the pulvinus of the leaf. 



Divisions of Leaves. — The leaf is entire (/. integrum) when its 

 blade is quite undivided (Oleander, fig. 82) ; — cut when its edge, 

 instead of being a continuous line, presents a series of broken 



96. ChestniTt. Dentate leaf. 



97. Arclif.ngel. Serrated leaf. 



Elm. Bideutate leaf. 



99. Hanthorn. Incised leaf. 



lines, owing to the parenchyma not accompanying the nerves to their extremities 

 (Chestnut, Oak„ Hawthorn) ; — dentate or toothed (/. dentatum) when it has sharp teeth 



