Myriophyllum. LV. ONAGRACE.E. 267 



delicate plant, common in wet, rocky woodlands in mountainous districts, N." 

 Eng., Brit. Am. W. to Or. Stem diaphanous, juicy, 5—10' high. Leaves 1— 

 2' long, § as wide, acute or acuminate, with small, remote teeth, pale green and 

 shining. Flowers white, rarely reddish, minute, in terminal racemes, Jl. 



Suborder,— H AliORAGE-U. 



Plants small, aquatic. Flowers minute, axillary, sessile. Calyx entire, or 

 3 — 4-lobed. Petals 3—4, often 0. Stamens 1 — 8, inserted with the petals into 

 the summit of the calyx. Ovary inferior, 1 — 4-celled. Fruit dry, indehiscent, 

 1 — 4-celied. Seed pendulous, 1 in each cell. 



8. PROSERPINACA. 

 Lat. Proserpina, a Roman goddess ; from some fancied resemblance. 



Calyx tube adherent to the ovary, 3-sided, limb 3-parted ; petals 

 ; stamens 3 ; stigmas 3 ; fruit 3-angled5 3-celled, bony, crowned 

 with the permanent calyx. — % Aquatic. Lvs. alternate. 



1. P. PALUSTRis. Spear-Uavcd Mcrmaid-^oeed. 



Lvs. linear-lanceolate, sharply serrate above the water, those below (if 

 any) pinnatifid.— Ditches, swamps and ponds, often partly submersed, N. Eng. ! 

 to Ark. Root creeping. Stems ascending at base, 6 — 20' high, striate, round- 

 ish. Leaves 10 — 15" by 2 — 3", acute at each end, lower ones on short petioles, 

 and if growing in water, pinnatifid with linear segments. Flowers greenish, 

 sessile, 1 — 3 together in the axils of the upper leaves, succeeded by a very hard, 

 triangular nut. Jn. Jl. 



2. P. PECTiNACEA. Lam. (P. palustris, 0. Mx.) Cut-leaved Mcrmaid-weed. 

 Ias. all pectinate, with linear-subulate segments ; fr. obtusely 3-angled, 



—Sandy swamps, in Ms. ! (rare) S. to Flor. Stems 5 — 10' high, ascending at 

 base from long, creeping roots. Leaves all finely' and regularly divided into 

 very narrow segments. Styles 0. Stigmas attenuate above. Fruit rather 

 smaller (less than 1" diam.) than in P. palustris, rugose when mature. Jl. Aug. 



9. MYRIOPHYLLUM. Vaill. 



Gr. fxvpios, a myriad, ^vXXoi', aleaf; from the numerous divisions of the leaf. 



Flowers c? , or frequently $ ; calyx 4-toothed in the $ and 9 , 4- 

 parted in the cf ; petals 4, often inconspicuous or ; stamens 4 — 8 ; 

 stigmas 4, pubescent, sessile ; fruit of 4 nut-like carpels cohering by 

 their inner angles. — % Submersed., aquatic herbs. Submersed lvs. paiied 

 into cajpillary segments. Upper fls. usually d, mddle ones $, lower 9- 



1. M. spiCATUM. — Spiked Wafer- Mi I foil. 



Lvs. in vcrticil.s of 3s, all pinnalely parted into capillary segments; Jls. 

 in terminal, nearly naked spikes ; Jloral lvs. or bracls ovate, entire, shorter than 

 the flowers ; lawcst ones subserrate and larger; pet. broadly ovate ; sta. 8; carpels 

 smooth. — N. Eng. to Ark., in deep water, the flowers only rising above the sur- 

 face. Stems slender, branched, very long. Leaves composed of innumerable, 

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



2. M. VKRTicir,LATi:M. Waler-Milfoil. 



Lvs. in verticils of 3s, lower ones pinnately parted into opposite, capillary 

 or .setaceous segments ; jls. in terminal, leafy spiKcs ; Jloral lvs. pectinate-pin- 

 natifid, mucli longer than the flowers; pet. oblong-obovate; sta. 8; carpels 

 smooth. — In stagnant water, Can. to Flor. W. to Oregon. Stem long, less slen- 

 der than in the last, only tin; upper part emerging. Flowers small, green, ax- 

 illary', with conspicuous floral leaves. Sepals acute. Anthers oblong. Jl. Aug. 



3. M. iiKTEROPHViJ.u.M. Mic/i.c. (Potamogeloii verticillatuin. WaU.^ 

 Lvs. in vcrticil.s of 5s, the lower ones pinnately parted into capillary 



lobes ; spikes terminal, nearly nakod ; Jloral lvs. ovate-lanceolatc, serrate. long«'r 

 than the flowers, crowded ; pel. ol)long; sta. 4 — 6; carprh scabrous, with 2 slight 

 ridges on the ha.-k.— In sluggish wat'M-. Can. to Floi. and Tc.\., rare. Stem 



