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plant. Brunella vulgaris, L. (heal-all) and Nepeta Catarta, L. 
(catnip) are the other two perennials of this class, both belonging 
to the mint family. The catnip being the larger weed, as might 
be expected it has the greater root. There is only one biennial in 
group 2, namely, Barbarea vulgaris, R. Br. (yellow rocket), 
which has a strong root like the chicory and mallow. 
The annuals, while not above the average in size, make a 
considerable list as follows: Brassica nigra, L. (black mustard), 
Capsella Bursa-pastoris, (L.) Mcench. (shepherd’s purse), Lepidium 
campestre (L.), R. Br. (field pepper-grass), Lepidium Virgint- 
cum, L. (pepper-grass), and Sisymbrium officinale (L.), Scop. 
(hedge mustard)—all of the same family, the Cruciferae, and 
very much alike in root habit. Lychnis Githago (L.), Lam. 
(corn cockle), is a tall, slender weed of the grain fields, and 
Abutilon Avicenne, Gert. (velvet leaf), a rank pest of cultivated 
ground. Among the Composite there are Anthemis Cotula, L. 
(mayweed), and Xanthium Canadense (Murr.), Gray, (cockle- 
bur), plants quite different in their size and capacity for mischief. 
Datura Tatula, L. (thorn apple), and Solanum Carolinense, L. 
(horse nettle), are two members of the nightshade family, the 
former a tall, much-branched, rapidly-growing weed, and the lat- 
ter a low spinose pest. There are three of the pigweeds, namely, 
Amarantus albus, L. (tumble-weed), A. chlorostachys, Willd. 
and A. retroflexus (common pigweeds), all of which have similar 
sizable roots, as has likewise their cousin, Chenopodium album, L. 
(goose-foot). The last of the list is Polygonum Convolvulus, L. 
(bind-weed), a miserable vine that is strongly and deeply rooted. 
There are six species in the group of weeds with moderately 
large root systems belonging to the fascicled type. Four of 
these are perennials, as follows: Asclepias Syriaca, L. (milk- 
weed). When grown in its best estate in the rich prairie soil, this 
should perhaps be ranked in the first group. The plant as 4 
whole is large, and grows in thick patches; the big roots make 
it difficult for the plow to be drawn among them. Linaria vulga- 
ris, Mill. (toad-flax), fills the soil with a mat of fibrous roots, 
some of which are of considerable size. Polygonum dumetorum 
var. scandens, (L.), Gray (climbing buckwheat), has also @ 
similiar root system. The quack grass (Agropyrum repens, (L-) 
