624 HALORAGIDACEAE, [ Myriophyllum. 
A widely distributed genus of from 25 to 30 species, found in fresh waters in nearly 
all parts of the world. Two of the New Zealand species are endemic, the rest extend 
to Australia, and one to South America as well. 
Leaves whorled; lower pectinately pinnatifid with capillary 
segments ; upper oblong, entire .. ~ he .. 1. M. elatinoides. 
Leaves whorled; lower pectinately pinnatifid with capillary 
segments ; upper linear, entire or serrate .. oe rs 
Leaves whorled, all pectinately pinnatifid. Nuts large, tubercled 
Leaves all opposite and entire, ;4,-4 in. long, linear. Stems 1-4 in. 
high. Male flowers seldom more than 2 o, as 
Leaves all opposite and entire, j4,-}in. long, narrow-oblong, 
Stems #?—-ld in, high. Male flowers 2-4 Ss vi 
Es 
1. M. elatinoides Gaud. in Ann. Sci. Nat. Ser. 1, 5 (1825) 105. 
—Forming dense masses in still waters. Stems rather stout, 6in. to 3 ft. 
long according to the depth of the water. Submerged leaves in whorls of 
4, rarely more, deeply pectinately pinnatifid, the segments capillary; the 
upper emerged or floral leaves in whorls of 4 or 3, sometimes opposite, much 
smaller, ¢-3 In. long, ovate or oblong to broadly lanceolate, sessile, obtuse, 
entire or the lower slightly toothed. Male flowers: Calyx-lobes very minute. 
Petals 4, oblong. Stamens 8. Female flowers: Calyx-lobes and petals 
apparently wanting. Nuts 4, small, oblong, smooth.—Hook. f. Fl. Nov. 
Zel. 1 (1853) 63; HI. Lasm. i (1860) 121; Handb. N.Z. Fl. (1864) 66; Benth. 
Fl. Austral. 1 (1864) 487; TL. Kirk Students’ Fl. (1899) 150; Cheesem. Man. 
N.Z. Fl. (1906) 151; Schindler in Pflanzenr. Heft 23 (1905) 91. 
. M. propinguum. 
. 4. robustum. 
hm GW DO 
. M. pedunculatum. 
. M. Votschiz. 
Cr 
NorRTH AND SouTH Isx~anpDs, Stewart IstaAnD: Common in rivers and lakes from 
the Auckland Isthmus southwards, ascending to 3500 ft. N ovember—February. Also 
in Australia and America from Mexico southwards. 
Subalpine specimens are stouter, with less delicate and more closely set submerged 
leaves, and the nuts are rather larger. 
2. M. propinquum 4. Cunn. Precur. (1839) n. 532.— Very variable in 
habit: in lakes and rivers forming masses of floating stems 1-4 ft. 
long, with numerous submerged leaves; in wet ground sometimes only 
an inch or two high, with the leaves all linear and entire. Leaves in whorls 
of 3-8, usually 4-5; submerged leaves deeply and finely pectinately pinna- 
tifid, segments capillary; upper emerged or floral leaves much smaller, 
+-4in. long, lanceolate and inciso-pinnatifid to narrow-linear and quite 
entire. Male flowers: Calyx-lobes evident. Petals white. Stamens 8. 
female flowers: Calyx-lobes and petals apparently wanting. Nuts 4, very 
small, linear-oblong, usually minutely scabrid or almost echinate, rarely 
quite smooth. — Schindler in Pfianzenr. Heft 23 (1905) 89. M. variaefolium 
Hook. f. in Hook. Ic. Plant. iii (1840) t. 289; Fl. Nov. Zel. i (1853) 64; FI. 
Pasm. 1 (1860) 122; Handb. N.Z. Fl. (1864) 66: Benth. Fl. Austral. ii 
(1864) 487. M. intermedium 7. Kirk Students’ FI. (1899) 150 (not of DC.). 
Fa oe | RZ WAAAAN ES ee A x 3 ~ “ 
NorTH AND SoutH Istanps, StEwart Istanp: Abpndant in lakes and streams, 
wet swamps, &c., from the North Cape southwards, ascending to 3000 ft. December— 
March. Also in Australia and Tasmania. 
3. M. robustum Hook. f. Handb. N.Z. Fl. (1864) 67.—Stems stout, 
erect, branched at the base, 6in. to 2 ft. high, rarely more. Leaves 
usually 5 in a whorl, 1-2 in. long, all deeply pectinately pinnatifid ; upper 
rather coarse, usually crowded and overlapping ; submerged leaves not 
often seen, when present with longer ¢apillary segments. Flowers rather 
large, $-4 In. long, solitary or rarely in pairs in the axils of the floral leaves, 
