GAMOPETALODS EXOGENS--PETALS MORE OR LESS 'UNITED.
Sambucus Canadensis. Common' Elderbrish, (s.) This indigenous shrub is very tenacious of life, and inclined to spread ezteneively aloog fence-rows and hedges, giving the premises a very slovenly appearance.
Dipsacus sytreetris. Mill Teasel, wild teasel, (b.) This coarse European weed is completely naturalized in some localities, nod is not only worthless, but threatens to become a nuisance if not attended t,o.
17.rnonla noveboracpsasss. Wild Iron Weed, (p.) A coarse native plaut, quite common iu moist, low grounds, and along fence-rows. The root of thie most be cut like the Canada thistle before the flowering eeasun in spring, or the danger will be immineot of Its over-running the whole area in a ehort period by means of its floating seeds Eepatoriem purpureum. Trumpet Weed, joe-pve weed, (p.) Several varieties of this tall, stont w._ed are indigenous oo our moiet low groande.
A.,ter eritoides. Heath-like Aster, (p.) Numerone species of this large American genus meet the eye of the farmer, in the latter part of summer, in his woudlands, low gronnds, borders of thickets, etC., some of which are quite ornamental, but the little bushy one here mentioned is about the only one which invades our pastures to any material extent. In neglected old fields, it often becomea as abundant as it is always a worthlees we«l.
E igpron canadense. Horse Weed, butter wt ed, (a.) This American weed has diffnsed itself all ON er Der coun try, and itis said, has reached and pervaded all Europe. The cultivation of hoed crope will clear the fields of this pest. Other varieties of the same genus infest meadows, which, if the evil becomes too burdensome, must be plowed np.
Rrigcron strigasum. Flea-bane Daisy, (a.) This very common native weed is apt to be abundaut in the first crop of upland meadow_ after the neual routine grain crop. After that, especially in good lands, it becomes more rare, being probably choked out, like many other weede, by the valuable grasses.
Solidago nemoralis. Golden Rod, (ix) Several epeciee of golden rod occur along fence rows, borders of woods and thickets, and ititrinle upon neglected pasture lielde.
Ambrosia trificia. Great Rag Weed, (a.) A coarse, ugly native weed, common in o a 4te places.
Am;rosia artemisiafolia. Bitter Weed, rag weed, (a.) This indigenous, bushy weed, occurs in moet cultivated groands, and is most abundant amoug the stubble, alter a crop of wheat. But if the laud be good, the plant seems to be smothered or choked ont the nest season by the neual ancceeding crop of clover and the grasses. It is always ready, however, to make its appearance whenever the grassy turf is broken np by tbe plow.
Xanthium strumariuna. Clot-weed, cockle-bur, (a.) This vile weed, of obscure origin, hes the appearance of a naturalized stranger in our country, and seems, fortun ately, not much inclined to spread. The burs are a great annuyance in the fleeces of sheep.
Xanthium spinosum. Thorny Clot-bur, (a.) Thie execrable foreign weed is fast becoming naturalized iu mauy portions of our country, particularly in the southern States. It may be frequently Peen also along the side walks awl waste places in the suburbs of our northern seaports. It is stated that the authorities of a southern c.ty a few yeare eince enacted an ordnance against the offensive wt ed, in which enactment it was denounced by the misnomer of Canada thistle. This plant may be destroyed with the hoe in the latter part of summer—in September.
Bidens frondosa. Bur Marigold, (a.) Worthless native weeds in gardens, corn fields, etc., and particularly disa greeable hy reason of the baited awns of the fruit, which adhere in great numbers to clothing.
Bidens oipinnatus. Spanish Needle, (a.) This, like the preceding, if not carefully watched and extirpated, is a great pest in cultivated lots. Another species, B. Cloy santhemo ides, known iis Beggar-ticks, if3 rather ehowy, with its head of yellow-rayed florets, and is frequently found a' ong swamps and rivulets in autumn. They are all regarded as nuisances on account of tbeir adhesive fruit. liaruta ,ofula. May-weed, fmtid chamomile, (a.) A disagreeable little foreign weed, which is extensively naturalized, and in had odor among us.