LECT. IV.] THE ROOT. BULBS. 173 



is well exemplified in the LiJy tribe. If we dig 

 up a plant of one of these, say the White Lily, 

 Lilium candidum, in summer, and examine its 

 bulb, we shall find that it consists of concave, 

 fleshy, overlapping scales, each of which is at- 

 tached at the base to a radical caudex, but is 

 loose at the apex*. A scale, when separately 

 examined, appears to be a homogeneous mass of 

 cellular texture enclosed in a cuticle ; the middle 

 being thick and fleshy, but the edges and the 

 apex nearly membranous; a construction, which, 

 on the convex surface, gives it a gibbous or keeled 

 character. The vessels run in longitudinal cords, 

 arranged at equal distances, through the scale ; as 

 may be seen in a transverse section of it, if the bulb 

 Have been placed for some hours in a coloured so- 

 lution-^. Removing the scales till the stem be ex- 

 posed, the new bulb is seen formed at its basis ; and, 

 by making a longitudinal section of the whole, the 

 manner in which the lateral offspring is connected 

 with the parent plant, through the medium of the 

 vascular system of the stem and of the caudex, is 



* Plate 2. fig. 1. The entire bulb of the Lilium candidum, 

 as it appears, when taken up in summer, during the vegetation 

 of the stem. 



f Fig. 2. A transverse slice of one of the scales, to 

 show the arrangement of the vessels in its substance. The 

 vascular bundles appear like dots ; and owing to the cellular 

 texture being more condensed in the immediate vicinity of 

 these, each bundle seems as if it were enclosed in a sheath. 



