186 



A TEXTBOOK OF BOTANY [Ch. IV, 10 



the supporting plant is ))r('cnriuus, aiul tlicy remain compact 

 with very short stems often coneealed completely by crowded 

 leaves. Their water supply comes from the rain which wets 

 the bark on which their roots grow ; but a few possess methods 

 of collecting the rain in funnel-shaped cups formed by their 



leaves (Fig. 127). All 

 epiphytes, indeed, show 

 marked water-conser\nng 

 features, including thick- 

 ened epidermis, sunken 

 stomata, storage tissues, 

 , ,1 ; jagjjjjpgpy^^^jK? jK?5^ and other features associ- 



^Ti \^M\^^r,n^^^'^^ ''^te<^l ^^''th plants which 



must stand frequent dry- 

 ness (page 69). Their 

 supply of mineral matters 

 is such only as they can 

 derive from the decaying 

 vegetation amongst which 

 they live, and much of it 

 comes from the bark into 

 which they send their 

 roots. Some kinds, how- 

 ever, collect among their 

 leaves the bark, tmgs, 

 flowers, etc., which fall 

 from above, while others 

 possess leaves so adjusted 

 to the supporting trunks 

 as to form half cups in which bark and other materials 

 streaming down with the rain are caught and held, later 

 decaying to a humus from which lioth water and mineral 

 matters are readily absorljed (Fig. 128). And many other 

 interesting features, some structural and some self-adjustive, 

 are known to accompany the epiphytic habit. From the 

 penetration of dead bark for rain water to a penetration of 



Fig. 128. — An opiijh>-tir Fern. Plaly- 

 ceriuvi grande, posyesKlng two kind of 

 fronds, — ordinary (drooping) and humus- 

 collecting (upright) : X 5- (From Goebel,) 



