ADDISONIA 67 
(Plate 74) 
PIAROPUS AZUREUS 
Light-blue Water Hyacinth 
Native of tropical America 
Family PONTEDERIACEAE = PICKEREL-WEED Family 
Pontederia azurea Sw. Fl. Ind. Occ. 609. 1797. 
Piaropus azureus Raf. Fl. Tell. 2: 82. Kye 
Eichhornia azurea Kunth, Enum. 4: 129. 1843. 
An aquatic plant, inhabiting shallow water, rooting in the mud, 
its stems stout, one to two feet long, or longer, sending out many 
roots from the nodes, and usually branched. e leaves are 
alternate, rather dark green; the petioles are stout, sheathing, 
from about four inches to over a foot long and half an inch thick 
in texture, orbicular, oval or obovate, from two to six inches long, 
very delicately and closely parallel-veined, with a tipped or some- 
times notched a y or abruptly narrowed base 
and a short or long style tipped by a small stigma. The fruit is a 
many-seeded capsule; when ripe the fruiting spike curves downward 
and becomes submersed. 
The plant inhabits lakes, ponds and rivers in Jamaica, Cuba, 
Hispaniola, and Trinidad, and is distributed on the continent from 
Nicaragua to Bolivia, Venezuela, and Uruguay. In Brazil, it 1s 
known under the names Culhereira and Camalote. It is related 
to the Floating Water Hyacinth, Piaropus crassipes, also native of 
continental tropical America but probably not of the West Indies, 
which has been introduced into Florida, Cuba, Bermuda and 
Jamaica, and has become one of the most troublesome of aquatic 
weeds, often blocking rivers and ditches by its vigorous growth, or 
