POND-WEED TRIBE 29 
stalks, bearing the fertilized stigma, sink within the bosom of the parent 
plant.” He adds, that the spadix lengthened itself even when the plant 
was placed in a basin of water. The Tassel-grass is not uncommon in the 
pools of salt-marshes ; except in west Scotland, where it is rare. 
In the sub-species R. rostellata, the sheath is not inflated, the fruiting 
stalk is not coiled spirally, but is short and waved; it flowers earlier, and 
the fruit has a longer beak. A variety of this (var. nana) found in Orkney 
has stems which creep along under the mud, and the foot-stalks are very 
short. 
3. HorNED POND-WEED (Zannichéilia). 
Common Horned. Pond-weed (Z. palistris)—Flowers axillary ; style 
half as long, and in one form quite as long as the fruit; leaves slender, 
opposite ; annual. This plant is very abundant in brackish pools in various 
parts of the kingdom, except that it is rare in West Scotland. Its habit is 
to grow entirely submerged in water, having much the appearance of the 
Lesser Pond-weed, P. pusillus; but during its flowering season, which is 
from July to September, it is readily distinguished from that plant by its 
small green flowers seated in the axils of its leaves. Its long thread-like 
branched stems, a foot or a foot and a half long, form tangling masses. The 
stigmas of the plant are very remarkable for their broadly expanded, uneven, 
cup-like form. The capsules are dry and one-celled, bearing usually but one 
seed, and each has an awl-shaped termination, which makes it look something 
like a bird’s claw. Mr. Baker recognises the following sub-species : Z. brachy- 
stemon, Z. pedunculata, and Z. polycarpa, based on minute differences in the 
floral organs. 
4, GRASS-WRACK (Zostéra). 
Broad-Ieaved Grass-wrack, or Sea-grass (Z. marina).— Leaves 
broad, linear, entire, nerved ; spadix bearing numerous flowers; rootstock 
creeping, perennial. All who have observed the long bright leaves and 
flexible stems of the Grass-wrack, floating gracefully in the sea, will acknow- 
ledge the appropriateness of the scientific name, derived from the Greek 
zoster, a riband. The leaves are long and blunt, with sheathing bases of 
bright but rathet deep glossy green. They grow from among mud at the 
base of rocks, and in sandy shallows, on sea-banks, and in salt-water ditches, 
sometimes covering acres of shallow water, and floating in pools among green 
laver and purple dulse, till some rough wave dashes over them, and, tearing 
up large masses, casts them upon the weedy shore. Sometimes the long 
leaves are seen floating above the mud right down in the deep sea, and seem 
welcomed by many a gliding little fish, or darting crustacean, or slow-moving 
mollusc, or quaint zoophyte— 
‘* Where ‘neath your keel the verdant sea-grass waves.” 
It has, however, no affinity with the sea-weeds among which it floats; for it 
has roots, and leaves, and flowers, the green flowers forming two rows on 
one side of the spadix. It is destitute of calyx and corolla, but is provided 
with anthers and pistils, which grow alternately, and the numerous seeds 
ripen amid the salt waters in September. These are round and white, and 
