534 



A TEXT-BOOK OF BOTANY. 



stem with palmately lobed or divided leaves, and large, irregular, 

 blue flowers which form a rather loose panicle (Fig. 297). The 

 sepals are 5 in number, the posterior upper one being large and 



E 



FIG. 297. Acomtum Napellus . A, one of the long-petiolate, divided leaves; B, epi- 

 dermal cells of lower surface; c, an epidermal cell of the upper surface; D, transverse sec- 

 tion through one of the principal veins showing two fibrovascular bundles, and strongly 

 collenchymatic cells beneath the lower epidermis; E, one of the few hairs from the petiole; 

 F, lignified bast fibers surrounding the sieve in the petiole; G, longitudinal section through 

 fibrovascular bundle showing spiral and reticulate tracheae (t), bast fibers (b) and some 

 of the collenchyma cells (c), those at the left exhibiting longitudinal pores which give 

 a crystal-like effect. 



helmet-shaped. The petals are 2 to 5 and rather small ; the two 

 posterior or upper ones which are hooded and concealed in the 

 helmet-shaped sepal are nectar-secreting (Fig. 223, E). The fruit 

 is a follicle and contains numerous small seeds. 



