(86) 



Five or six glandular ducts may be seen in the cross section 

 of the cortex in agreement with the rhizome while the aerial 

 stems usually show but four. One or more of these ducts 

 occur in the pith in both kinds of stems. Whether or not the 

 secretion exercises a protective function has not been ascer- 

 tained. 



Perhaps the most marked structural adaptation of the bulbil 

 is the entire absence of stomata or transpiratory openings in 

 the epidermis, which is also true of the short bracts; the inner 

 surfaces of the scales sheathing the terminal buds are furnished 

 with capitate glandular hairs however. 



As has been noted the bulbils are but sparsely provided 

 with reserve food, and while they may remain quiescent 

 throughout the winter in equable temperatures, yet they may 

 be induced to germinate in a few days or a few weeks after 

 separation from the parent plant. The first indication of 

 activity consists of the formation of roots at the basal nodes, 

 but these organs are formed from all of the internodes before 

 the apical bud is fairly in action. Germination proceeds in- 

 differently in water and soil. The bulbils have a specific 

 gravity greater than water and usually sink when first sepa- 



^c§233> 



Fig. 6. Advanced stage in germination of bulbil in water, showing spiral 

 form of roots, and geotropic curvature of shoot. X 2 - 



rated from the plant but rise to the surface when germination 

 begins, by reason of the gases accumulated, although they rise 

 and sink erratically if allowed to continue growth in water. 

 The roots appear to be subject to the usual contraction of 

 the cortex which takes place so irregularly, however, that these 

 organs are thrown into spirals. The tangle produced by the 

 twisted roots is most effective in causing a floating germin- 

 ating bulbil, to become entangled in the branches or roots of 



