Seeds brown to black, more or less slightly granular, shining, flattened on two sides, circular edge bluntly rounded, with a single notch from which on one side extends a slight depression toward the center of the face, .5-.8 mm. in diameter. Introduced from Europe. Occasional on moist soil.
=Maple-leaved Goosefoot.= _Chenopodium hybridum_ L. Concerning the different stages of cleaning, note remarks above under C. album.
Seeds black, shining, greenish gray if not fully cleaned, nearly circular, lens-shaped, equally convex, 1.2-1.8 mm. in diameter, with a notch on the edge, from which on one side a groove leads to near the center of the face, surface finely uneven, often with a faintly evident radiating striation. Native of this country. Of little importance.
=Many-seeded Goosefoot.= _Chenopodium polyspermum_ L. Concerning different stages of cleaning, note remarks above under C. album.
Seeds finely glandular, shining, jet-black, greenish gray, when not fully cleaned, nearly circular or broadly kidney-shaped, sides equally convex, .6-1.1 mm. in diameter, with a notch on the edge from which on one side, a groove leads to near the center of the face. Introduced from Europe.
=Winged Pigweed.= _Cycloloma atriplicifolium_ (Spreng.) Coulter. Seeds are likely to occur in either of three different guises depending upon the degree their ripeness or the amount of threshing to which they have been subjected. See the figure of this species. Seeds granular, circular, dull, jet-black, or gray in case the thin ovary remains, 1.3-1.7 mm. in diameter, lower face convex, the upper slightly convex if mature, with a slight notch on the rounded edge, the lower face bearing a slight curved groove, leading from the notch to near the center, the upper face with a light spot at the center. Introduced from western United States. A tumble weed, not common.
=Russian Thistle.= _Salsola Kali tenuifolia_ G. F. W. Mey. This is not a thistle nor a cactus, but a pigweed. Concerning different stages of cleaning, note remarks above under Chenopodium album (see the figures). Seeds conical, the apex flattened or concave, both sides showing the long coiled embryo, light gray in color, about 2 mm. in diameter. Introduced from northern Europe into the north west and from there into Michigan. Well advertised, though not of high rank as a weed in this state. A tumble weed.