HALORAGEJi. V. PROSERPINACA. VI. MYRIOPHYLLUM. 



703 



in ditches and ponds ; and of Mexico in slow running water. 

 Ell. sketch. 1. p. 181. Torr. fl. unit. st. 1. p. 161. P. paliistris 

 var. a, Michx. fl. bor. amer. 1. p. 76. Trixis, Mitch. I.e. with 

 a figure. Trixis palustris, Gaertn. fr. 1. p. 115. 



Marsh Proserpinaca. Fl. July. Clt. 1818. PI. cr. 



2 P. PECTIN A' TA (Lam. ill. 1. p. 214. t. 50. f. 1.) leaves all 

 pinnatifidly pectinated ; angles of nut blunt. 2.W. H. Na- 

 tive of South Carolina, Georgia, New Jersey, and Pennsylvania. 

 Ell. sketch. 1. p. 182. Torrey, fl. unit. st. 1. p. 162. P. palus- 

 tris j3, Michx. 1. c. Only a variety of the preceding according to 

 Michx, but according to Lamarck, Elliott, and Torrey it is a 

 proper species. 



Pectinate-leaved. Proserpinaca. Fl. July, Aug. Clt. 1822. 

 PI. cr. 



Cult. These plants should either be grown in large pans of 

 water, with an inch or two of mould in the bottom for the roots to 

 run in, or in pots set in pans of water, or they may be grown in 

 ponds. They require some care and shelter to preserve them 

 through the winter in Britain. 



VI. MYRIOPHY'LLUM (from pvpwt, myrios, a myriad, 

 and tj>v\\ov, phyllon, a leaf ; in reference to the numerous divi- 

 sions of the leaves). Vaill. act. acad. par. 179. t. 2. Lin. 

 gen. no. 1066. Gaertn. fr. 1. t. 68. Lam. ill. t. 775. D.C. 

 prod. 3. p. 68. Pentapterophyllum, Dill. nov. gen. 7. Pentap- 

 teris, Hall. helv. 1. p. 454. 



LIN. SYST. Monce^cia, Tetrdndria, and Octt'mdria, Tetragynia. 

 Flowers monoecious, rarely hermaphrodite. Male. Calyx 4- 

 parted. Petals 4, caducous, ovate, alternating with the calycine 

 lobes. Stamens 4-6 or 8. Female. Calyx adhering to the 

 ovarium ; limb 4-lobed. Petals none. Fruit separable into 4 

 hard, 1 -seeded, indehiscent nuts. Albumen almost absent. 

 Floating aquatic herbs, rising above the water to flower. Leaves 

 finely cut, opposite or verticillate. Flowers small, disposed in 

 axillary whorls ; or in whorled spikes, in consequence of the 

 upper leaves being almost abortive ; upper ones male, lower ones 

 female. 



SECT. I. PENTA'PTERIS (from irevrn, pente, five, and Tcrtpov, 

 pteron, a wing ; application not evident). D. C. prod. 3. p. 

 68. Flowers usually monoecious. Anthers oblong. Leaves 

 opposite or often in whorls. 



* Male flowers octandrous. 



1 M. SPICA'TUM (Lin. spec. 1409.) leaves finely cut into ca- 

 pillary segments, disposed in whorls ; flowers in whorled inter- 

 rupted, almost leafless spikes ; floral leaves shorter than the 

 flowers, lower ones a little serrated, the rest quite entire. If . 

 W. H. Native of Europe and North America, in ditches, lakes, 

 and pools, never in flowing water ; plentiful in Britain. Fl. dan. 

 681. Smith, engl. bot. t. 83. Schkuhr, handb. t. 296. Petals 

 reddish. 



Spiked Water-milfoil. Fl. June, Aug. Britain. PI. fl. 



2 M. PECTINA'TUM (D. C. fl. fr. suppl. 529.) leaves finely cut 

 into capillary segments, disposed in whorls ; flowers in whorled, 

 interrupted, almost leafless spikes ; floral leaves a little longer 

 than the flowers, all pectinately serrated. If .W. H. Native about 

 Montpelier, in still water, and Denmark, and probably through 

 the whole of Europe. Habit of the preceding species, but dif- 

 fering in the floral leaves. It appears to be intermediate between 

 M. spicatum and M. verticillatum. 



Pectinate-leaved Water-milfoil. PI. fl. 



3 M. ALTERNIFOLIUM(D. C. fl. fr. suppl. p. 529.) leaves finely 

 cut, disposed in whorls ; flowers in nearly leafless spikes, alter- 

 nate, lower ones in fascicles, the rest solitary ; lower floral leaves 

 pinnatifid, exceeding the flowers, upper ones entire, short. If. 



W. H. Native of the west of France, in still water about 

 Nantes, and in Vascony. M. alternifolium, Steud. nom. 

 Alternate-leaved Water-milfoil. PI. fl. 



4 M. VERTICILLA'TUM (Lin. spec. 1410.) leaves finely cut into 

 capillary opposite segments ; flowers in axillary whorls ; floral 

 leaves all pinnatifid, much longer than the flowers, and hardly 

 distinguishable from the other leaves. If. . W. H. Native of Eu- 

 rope and North America, in pools, lakes, and ditches, but never 

 in running water. Smith, engl. bot. 218. Clus. hist. 2. p. 252. 



Far. ft, limbsum (Hect. in litt.) lobes of leaves linear, acute, 

 and regular. 2f . H. Native of Europe, in almost dry places. 

 Whorled-Aowered Water-milfoil. Fl. Ju. Aug. Brit. PI. fl. 



5 M. QUITE'NSE (H. B. et Kunth, nov. gen. amer. 6. p. 89.) 

 leaves finely cut into filiform lobes, about 1 5 lobes on each side. 

 "H. . W. S. Native of the Andes about Quito, in the river Guan- 

 cabamba. 



Quito Water-milfoil. PI. fl. 



6 M. TNDICUM (Willd. spec. 4. p. 407.) leaves in whorls, 

 lower ones finely cut into capillary segments, upper ones lanceo- 

 late, cuneated, rather cut at the apex ; flowers axillary, verticil- 

 late, ty. W. S. Native of Ceylon and Coromandel. The 

 flowers are said to be hermaphrodite. 



Indian Water-milfoil. PI. fl. 



7 M. ELATINOIDES (Gaud. fl. mal. p. 17. ann. sc. nat. 5. p. 

 105.) leaves 4 in a whorl, lower ones cut into capillary segments, 

 upper ones pinnatifid, toothed or entire, oblong-lanceolate ; 

 flowers dioecious, female ones axillary. Tf. . W. F. Native of 

 the Maclove and Falkland Islands. Male flowers unknown. 



Elatine-like Water-milfoil. PI. fl. 



8 M. TERNA'TUM (Gaud. 1. c.) leaves 3 in a whorl, lower ones 

 cut into capillary lobes, upper ones oblong, quite entire ; flowers 

 axillary, upper ones male, octandrous, lower ones female. Tf. . 

 W. F. Native of the Falkland Islands. 



Ternate-\ea\ed Water-milfoil. PI. fl. 



9 M. AMPHI'BIUM (Labill. nov. holl. 2. p. 70. t. 220.) leaves 

 opposite, obovate, entire; flowers axillary, solitary. If. B. G. 

 Native of Van Dieman's Land, in marshes. A creeping herb, 

 with the habit of Callltriche. Flowers monoecious, male ones 

 octandrous. 



Amphibious Water-milfoil. PI. cr. 



* * Male flowers hexandrous. 



10 M. HETEUOPHY'LLUM (Michx. fl. bor. amer. 2. p. 191.) 

 leaves in whorls, cut into capillary segments ; spikes terminal, 

 almost naked ; floral leaves opposite, ovate, acute, sharply ser- 

 rated, exceeding the flowers. % . W. H. Native of Carolina 

 and Georgia, in still water. Potamogeton verticillatum, Walt. 

 car. p. 90. 



Variable-leaved Water-milfoil. PI. fl. 



* * * Male flowers tetrandrous. 



11 M. TUBERCULA'TUM (Roxb. fl. ind. 1. p. 471.) leaves in 

 whorls, lower ones pinnatifid ; spikes almost naked ; bracteas 

 oblong, a little toothed at the apex ; carpels tubercular, acute on 

 the back. I/ . B. S. Native of humid places and on the shores 

 of lakes, near Calcutta. Flowers pink. 



Tubercled-fruhed Water-milfoil. PI. fl. 



12 M. INTERME V DIUM(D. C. prod. 3. p. 69.) leaves in whorls, 

 lower ones cut into filiform lobes ; floral ones oblong-linear, ser- 

 rated, acuminated at both ends ; carpels rather tubercular, blunt 

 on the back. If. W. S. Native of the East Indies. Ammannia 

 pinnatifida, Lin. fil. suppl. 127.? Hottonia sessiliflora, Vahl. 

 symb. 2. p. 36. Willd. spec. 1. p. 813. ? 



Intermediate Water-milfoil. PI. fl. 



13 M. TETRA'NDRUM (Roxb. fl. ind. 1. p. 470.) leaves dis- 



