Ordee 52.— ONAGRACEiE. 3C7 



1 to 2' loDg, 5 as wide, acute or acuminate, with email, remote teeth, palo grwu 

 and shining. Fla white, rarely roddisli, minute, in terminal racemes. Jl. 



9. PROSERPINA'CA, L. Mermaid Weed. (Lat. Proserpina, .i 

 Roman goddess; from some fancied resemblance.) Calyx tube ad- 

 herent to the ovary, 3-sided, limb 3-parted ; petals none ; stamens 3 ; 

 stigmas 3 ; fruit 3-angled, 3-celled, bony, crowned with the permanent 

 calyx. — 1i Aquatic. Lvs. alternate. 



1 P. paltiBtris L. Lvs. linear-lanceolaie, sharply serrate above the water, those 

 below (if any) pinnatifid. — Ditches, awamps and ponds, often partly submerged, 

 iST. Eng., Fla. and La. Rt. creeping. Sts. ascending at base, G to 20' high, 

 striate, roundish. ■ Lvs. 10 to 16" by 2 to 3", acute at each end, lower ones on 

 short petioles and, if growing in water pinnatifid with linear segments. Fls. 

 greenish, sessile, 1 to 3 together, in the axils of the upper leaves, succeeded by 

 a very hard, triangular nut. Jn., Jl. 



2 P. peotinacea Lam. Lvs. allpeotinate, with linear-subulate segm. ; fr. obtusely 

 3-aDgled. — Sandy swamps, in Mass, (rare) S. to Fla. St. 6 to 10' high, ascendini; 

 at base from long, creeping roots. Lvs. all finely and regulai-ly divided into very 

 narrow segments. Sty. ; stig. attenuate above. Fr. rather smaller (less than 

 1" diam.) than in P. palustris, rugous when mature, JL, Aug. 



10. MYRIOPHYL'LUM, Vaill. Water Milfoil. (Gr. fxvpiog, innu- 

 merable, (pvXXa, leaves.) Flowers 8 , or frequently i^ ; calyx 4-toothed 

 in the !^ and ? flowers, 4-parted in the $ ; petals 4, often inconspicu- 

 ous or none ; stamens 4 to 8 ; stigmas 4, pubescent, sessile ; fruit of 4, 

 nuHike carpels, cohering by their inner angles. — V submersed, aquatic 

 herbs. Submersed lvs. parted into capillary segments. Upper fls. u.sii- 

 ally S , middle ones § , lower ? . 



§ stamens 8. Carpels smooth and even. Leaves whorled in 8s .Nos. 1, 2 



§ Stamens 4. — Carpels ridged on the back. Lvs.. -whorled in 43 and lis Nos. 3, 4 



— Carpels smooth and oven. Lvs. alternate or wanting Nos. 5, G 



1 M. spicdtum L. Lvs. in verticils of Ss, all pinnately parted into capillary seg- 

 ments; J!s. in terminal, nearly naked spikes; floral lvs. or bracts, ovate, entire, 

 shorter than the fls., lowest ones subserrate and larger; petals broadly ovate ; 

 fitam. 8 ; carp, smooth. — N. Eng. to Ark., in deep water, the fls. only rising above 

 the surface. St. slender, branched, very long. Lvs. composed of innumerable, 

 hair-like segments, always submerged. Fls. greenish, sessile. Jl., Aug. 



2 M. verticilldtum L. Lvs. in verticils of 33, lower ones pinnately parted into 

 opposite, capillary or setaceous segments; fls. in terminal, leafy spikes; floral Ic. 

 peciinate-pinnatiful, much longer than the fls. ; petals oblong-obovate ; stam. s ; 

 carp, smooth. In stagnant water, Can. to Fla., W. to Or. St. long, less slender 

 than in the last, only the upper part emerging. Fls. small, green, axillary, with 

 conspicuous floral lvs. Sep. acute. Anth. oblong. Jl., Aug. 



3 M. heteropli;}-Iluin Mi. Lvs. in verticils of 5s, the lower ones pinnately 

 parted into capillaiy lobes ; spikes terminal, nearly naked ; floral lvs. ovaM-laticeo- 

 late, serrate, longer than the fls., crowded ; petals oblong ; stam. 4 to G ; carji. 

 scabrous, with 2 slight ridges on the back. — In sluggish water, Can. to Fla. ami 

 Tex., rare. St. thick, branching. Lvs. very various, lowest floral ones pccti- 

 nately divided. Petals somewhat persistent. Sepals minute. Bractlets serrulate. 

 Jn. — Sept. 



4 M. scabratum Mx. Lvs. pinnatifid in whorls of 43 and 5s ; fls. verticUlate, 

 axillary, upper fls. $, with 4 stam.', lower ones S ; florai lvs. linear, pectinatehj 

 toothed; fr. 8-angled, the ridges tuberculate. — Plymouth, Mass. (Oakes), Block 

 Island (Robbins), S. and W. States. St. 6 to 12' high. Segm. of the lvs. linear- 

 capillary. 



5 M. ten^llum Bw. Erect and almost leafless; floral lvs. or bracta alternate, 

 minute, entire, obtuse ; fls. ,5 ; petals linear ; stam. 4 ; carp, smooth, not ridged. — 

 About the edges of ponds and rivers, Providence, B. I. (Olney), northern part of 



