STRUCTURE.] WARTS LENTICULAR GLANDS. 163 



volume of Lady's Botany (t. 47.). The opening through the 

 cuticle immediately above them shows that they are internal 

 organs ; nevertheless, Meyen considers them external glands. 

 Internal glands are very common in Labiates. 



Sessile glands, verruca, or warts, are produced upon various 

 parts, and are extremely variable in figure. In Cassias, they 

 are seated upon the upper edge of the petiole, and are usually 

 cylindrical or conical; in Cruciferous plants they are little 

 roundish shining bodies, arising from just below the base of 

 the ovary ; in the leafless Acacias they are depressed, with a 

 thickened rim, and placed on the upper edge of the phyllode ; 

 they are little kidney-shaped bodies upon the petiole of the 

 Peach and other drupaceous plants ; and they assume many 

 more appearances. They are common upon the petiole, as 

 in Passiflora ; they are also found upon the calyx, as in some 

 species of Campanula, and at the serratures of the leaves, 

 when they are considered by Roper (De Floribus Balsaminea- 

 rum, p. 15.) to be abortive ovules; and they appear upon the 

 pericarp and the skin of the seed ; in the latter case they are 

 called spongiola seminales by De Candolle. In figure they 

 are round, oblong, or reniform, and occasionally cupulate, 

 when they receive the name of glandes a godet ( glandules 

 urceolares) from some French writers. Warts are the glandes 

 cellulaires of Mirbel ; but they must not be confounded with 

 the glandes vasculaires of the same writer, which are not 

 mere excrescences of the epidermis, but modifications of well 

 known organs. (See Discus, further on.) Of this nature 

 are the hypogynous glands of Cruciferous plants already 

 referred to. 



Lenticular glands (Lenticelles of De Candolle ; Glandes 

 lenticulaires of Guettard ;) are brown oval spots found upon 

 the bark of many plants, especially willows : they have been 

 thought to indicate the points from which roots will appear 

 if the branch be placed in circumstances favourable to their 

 production, and are considered by De Candolle to bear the 

 same relation to the roots that buds bear to young branches. 

 (Premier mem. sur les Lentic., in the Ann. des Sciences 



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