JU8 CAI.I.ITIJICIIACK.K. (WATKR-STAUAVOHT FAMir.Y.) 



1. SAURURUS, L Li/.akd'8-Taii,. 



Stamens i - 8, with loii^' iliil»-.slia|n'(l filaments. Fruit somewhat fleshy, com- 

 posed of 3 - 4 partly united 1 - 2-seeded carpels, pointed with as many stignms 

 — Flowers wliitf. 



1. S. cernuus, L Stem erect, lirancliiii<;; leaves petiolcd, cordate-ovate, 

 or oblonjT-ovate, acuminate ; spikes white, terminal, nodding at the apex ; flow- 

 ers numerous, each from the axil of a small hrait. — Marshes and muddy hanks, 

 Florida, and northward. May-Auy. — Rhizouia creeping'. Stem l°-2°high. 

 Spikes 4' -6' long. 



OuDKii 110. CERATOPHYI.T^ACE.li:. (IIornwort 



Family.) 



Submerged aquatic herbs, witli filiform jointotl and branching stems, 

 finely dissected whorled leaves, and small axillary monnecious flowers, 

 destitute of floral envelopes, but surrounded by an involucre of 8-12 

 linear leaves. Anthers 1 2 - 24, oblong, 2 - 3-toothed, sessile. Ovary 

 solitary, simple, with a single suspended orthotropous ovule. Achenium 

 compressed, pointed with the slender persistent style. Albumen none. 

 Cotyledons 4. Plumule eonsjiicuous. — Consisting of the single genus 



1. CERATOPHYLLUM, L. IIornwort. 



1 . C. demersum, L. Leaves rigid, G - 9 in a whorl, once or twice forking, 

 with the lobes B])iny-toothed ; achenium oval, compressed, tubercular-roughened 

 on the sides, and armed near the base with 2 lateral widely-spreading slender 

 spines. — In Stillwater, Florida, and northward. Sept. and Oct. — Stems l°- 

 4° long. Leaves near the end of the branches much crowded. 



2. C. echinatum, Gray? Leaves weak, 9-12 in a whorl, 3-4 times 

 forking, the ultimate segments bristly-toothed; ovaries warty, tmarmod; ache- 

 nium oblong, tubercular-roughened on the sides, the edges margined and armed 

 with 5-7 strong and spreading spines. — Shallow ponds, on St. Vincent's Isl- 

 and, West Florida. May. — Stems 6' - 12' long. 



3. C. SUbmersum, L. Leaves hair-like, 3-4 times forking, bristly- 

 toothed ; achenium oblong, slightly compressed, tubercular-roughened, with 

 rounded margins, unarmed. — South Florida, Dr. Blodgett. — Stems 6' -12' 

 long. 



Order 117. CALLITRICHACE^. (Water-Staravout 



Family.) 



Small aquatic annuals, with opposite entire leaves, and solitary axillary 

 polygamous flowers without floral envelopes. Stamen mostly solitary, 2- 

 bracted in the sterile flower. Filament slender : anther reniform, the 



