256 
Prankerd. — On the Structure and Biology of 
stalked, capitate glands. The stalks are unicellular on the aquatic and 
multicellular on the aerial stem (Fig. 13). 
The structure of the land forms is in every way similar to that of the 
submerged, and not to the aerial part of the aquatic plants, which latter 
Tu pes o| £>tele j^Durul in -H ol tonia 
M apliostele j-ounA «n 
youmj plant ej botljT specie S. 
^jcTullafed. stele in 
aquatic stem oj Utl^ species 
endocUrmift... 
pl,Um 
XMie»n • - - 
V/' /. 
(*52; 
EclopMoic Sipfyonostele 
|ouni at base q in|lorescence 
"7 ii. palustris 
"Trace o) 
Jourul at tase q inj 
>f AmpbtpUoic SipKonoslele 
inTforescenee irj Jf injlata 
presents a striking contrast to that already described. Diagram 6, above, and 
Figs. 1 and 20. Pis. XX and XXI, illustrate the structure of the internodes, 
where we have a ring of V-shaped bundles separated by the wide medullary 
rays, surrounding a hollow pith. The cells of the innermost layer of the 
cortex fit closely together (en, Fig. 20), otherwise there is no characteristic 
