OUR AMPHIBIOUS PERSICARIAS 21 
the summit: nodes abruptly swollen, internodes about 5 cm. 
long: leaves 12-20 cm. long with a petiole of 2-3 cm. included; 
blades cordate oblong, subcordate varying to obtuse and the upper 
even acutish at the base, vivid green, glabrous or beset with 
numerous short soft hairs (leaves not even roughish to the touch) 
hairs on the midvein scouter roughish, petioles rough scabrous. 
This phase found usually around deep muddy ponds where 
the fertile aquatic phase grows. The plant becomes ranker in 
growth as it approaches to the water, and gradually merges into 
what may be called the strictly fertile aquatic phase. Plants on 
dry land never produce flowers, and sparingly so in mud. Ter- 
restrial plants creeping in mud covered with several inches of water 
have been found with smaller spikes of rose to deep purple flowers. 
Aquatic Phase. Internodes much longer, fistulous in the 
floating form often 2-3 metres long, rooting from the nodes, the 
branching roots floating like plumes in the water: leaves 10-25 
em. long and the larger 7 cm. broad cordate oblong; with blunt 
points on the basal lobes giving the larger leaves a subsagittate 
appearance; leaves glabrous, slimy, dark green, the margins 
somewhat scabrous-serrulate with hair points, acute at the apex: 
petiole 7-10 cm. long, spikes linear, 3-9 cm. loag rich rose red, 
bracts hirtellous uncommonly long pointed cuspidately rather 
than acuminately: peduncles slender strigose glandular or hirtellous 
often one of the spikes glandular and the other at least partly. 
The above description holds good only regarding the submerged 
and the flowering part of the aquatic phase. As the stems rise 
assurgently out of the water nearly a metre deep, and exposing 
the tops of the stems above the water to the height of 3-5 dm. the 
upper five or six leaves take on the character of the foliage of the 
terrestrial sterile phase regarding pubescence, shape ete. All 
the gradations of character may be found in passing from these 
more or less pubescent leaves to the larger, slimy, glossy, aquatic 
leaves below on the same shoot. The submerged leaves as the 
stem sinks, by the weight of the flowering top, soon turn yellow 
and decay. 
The flowering phase thrives best in nearly a metre of water. 
Only the submerged stems are thickly fistulous often nearly 1.5-2 
em. thick and bright green. This peculiar habit of the aquatic 
in growing out of water with the leaf variation is characteristic. 
