CHAP. II. GLANDS. 49 



particles which give a leprous appearance to the surface of 

 certain plants, as the Elasagnus and the Pine Apple. (Plate I. 

 fig. 10. b.) They consist of a thin transparent membrane, 

 attached by its middle, and, owing to the imperfect union, 

 towards its circumference, of the cellular tissue of which it is 

 composed, having a lacerated irregular margin. A scale of 

 this nature is called in Latin composition lepis, and a surface 

 covered by such scales lepidotus — not squamosus, which is 

 only applied to a surface covered with the rudiments of leaves. 

 Scurfs are the polls en ecusson {pili scutati) of De Candolle. 



Ramenta {VaginellcB) are thin, browTi, foliaceous scales, 

 appearing sometimes in gi'eat abundance upon young shoots. 

 They are particularly numerous, and highly developed, upon 

 the petioles and the backs of the leaves of Ferns. They con- 

 sist of cellular tissue alone, without any vascular cords, and 

 are known from leaves not only by their anatomical structure, 

 but also by their irregular position, and by the absence of buds 

 from their axils. The student must particularly remark this, 

 or he will confound with them leaves having a ramentaceous 

 appearance, such as are produced upon the young shoots of 

 Pinus. Link remarks, that they are very similar in structure 

 to the leaves of mosses. The term striga has occasionally been 

 applied to them {Dec. Theor. Elem. ed. 2. 376. Link, Elem. 

 240.) ; but that word was employed by Linnfeus to designate 

 any stiff bristle-like process, as the spines of the Cactus, the 

 divaricating hairs of Malpighia, and the stiff stellated hairs of 

 Hibiscus. So vague an application of the term is very properly 

 avoided at the present day, and the substantive is rejected 

 from modern glossology; the adjective term strigose is, how- 

 ever, occasionally still employed to express a surface covered 

 with stiff hairs. 



5. Of Glands. 



Glands are small collections of firm cellular tissue, which 

 is often much harder and more coloured than that which sur- 

 rounds it. They are of several kinds. 



Stalked glands are elevated on a stalk which is either simple 

 or branched : they secrete some peculiar matter at their ex- 



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