Biological Papers. 115 



676. Piaropus crassipes Britt. (Eichhornia Solms.) Water-hyacinth. 

 Planted in little lakes here and there in E. K, and S. E. K., as at Merriam 

 Park, Gage Park, etc. Does not survive the winter. Leaves reniform. 



677. Pontederia cordata L. Pickerel-weed. Borders of ponds, S. E. K. ; 

 not common. July. Leaves cordate-sagittate 



Order XXV. NYAMPH^ALES. The Water lilies. 

 Inflorescence solitary, at the ends of long scapes or peduncles. Flowers 

 commonly floating, perfect; perianth normally six-parted, hypogynous. 

 Stamens six to many, hypogynous, part of the many stamens barren and 

 more or less transformed into petals (staminodia). Anthesis periodical, day 

 opening. Pollination entomophilous, rarely hydrophilous. Carpels three or 

 more, distinct or united; ovules solitary or several in each ovulary. Fruit 

 nut-like, indehiscent, with one or more seeds. (This order has many dicotyl 

 characters, such as partially net-veined leaves, numerous petals, radiate 

 stigmas, etc., allying it to the Ranales and Papaverales; yet, notwith- 

 standing this, the plants are, in structure, mainly monocotyledonous. 



Family 50. Nymphaeace.'e. Water-lily Family, 

 (a) Cabomboidese. Water-shield Subfamily. 

 Stems slender, a meter or so in length, branching, and with the peduncles, 

 petioles and under surface of the leaves coated with gelatinous matter. 

 Floating laminae peltate; submerged leaves palmately dissected into numer- 

 ous capillary segments. Flowers axillary, small, various colors. Petals 

 and sepals each three. Stamens three to eighteen. Carpels three to 

 eighteen, separate; ovules commonly three, pendulous. Fruit one- to three- 

 seeded, indehiscent. 



678. Cabomba caroliniana Gray. Carolina Water-shield; Parrot-feather. 

 Ponds and slow streams, S. E. K. ; occasional. May. (S) 



679. Brasenia purpurea Caspary. {B. peltata Pursh.) Water-shield'.. 

 Ponds and slow streams, Cherokee to Montgomery county; occasional. 

 Summer. 



680. Brasenia schreberi Gmelin. Water-target. Grown occasionally in 

 the little artificial ponds, in company with water-lilies, on account of its. 

 peltate floating floral leaves. 



(b) Nyynphseoidese. Pond-lily Subfamily. 

 Rootstocks perennial and very thick, creeping in the soft, black earth in 

 the bottom of ponds, with the water preferably one to two meters deep. 

 Leaves very large and floating; petioles as long as the depth of the water ; 

 laminae flat on the surface, auriculately lobed, orbicular to lance-ovate, the 

 basal lobes often touching, leaving a deep sinus at the base of the lamina ; 

 nervation radiating, pinnate, and dichotomous ; submersed leaves similar, 

 but with shorter petioles. Perianth of three sepals and three petals ; petalo- 

 dia and staminodia, or petal-like and neutral stamens, numerous ; fertile 

 stamens many, always in whorls of three. Carpels many, united into a 

 compound globose fruit ; styles none ; stigmas as many as the carpels, 

 linear, radiating, poppy-like, on a disk on the upper surface of the ovula- 

 ries. Seeds ovoid-globose, stipitate or sessile ; embryo central ; endosperm 

 moderate. 



