=Thyme-leaved Spurge.= _Euphorbia serpyllifolia_ Pers. Seed ash-colored, obovoid, four-angled or nearly square in cross-section, the surface covered with four or five more or less broken obtuse transverse ridges, a slender, dark line (raphe) extending from end to end on one corner. Dry soils, like railway tracks. CASHEW FAMILY. ANACARDIACEAE. [Illustration: Fig. 127.] =Poison Ivy.= _Rhus Toxicodendron_ L. Berry nearly white, globular, about 5 mm. in diameter, drupe kidney-shaped, concave on both edges, 3 by 4.5 mm. in diameter, 2 mm. thick. To some people very poisonous to the touch; a woody shrub. MALLOW FAMILY. MALVACEAE. [Illustration: Fig. 128.] =Indian Mallow. American Jute. Velvet Leaf.= _Abutilon Theophrasti_ Medic. _Abutilon Abutilon_ (L.) _Rusby_. Flowers yellow; seeds brown, flattened, 3.5-4 mm. long, ovoid excepting a piece cut from one side of the smaller end with 3-4 curved rows of minute slender objects on each side, the raphe extending from the pointed end to the notch on one side (half anatropous). Naturalized from northern Asia. [Illustration: Fig. 129.] =Bladder Ketmia.= _Hibiscus Trionum_ L. Seed brown, the surface dotted with numerous, ragged, light-colored pimples. Think of the shape as obovoid, and then bent somewhat to the side. As now found the seed is triangular in outline with rounded corners, considerably thinned toward one corner near which is the seed scar in the midst of a depression. Each side of the triangle is about 2 mm. long. Introduced from Europe. Not yet a prominent weed in Michigan. [Illustration: Fig. 130.] =Cheeses. Running Mallow.= _Malva rotundifolia_ L. Flowers white; cluster of 12-15 fruits flattened, circular with depression on each side, ovary circular, wedge-shaped, very slightly roughened, with radiating ridges; seeds light brown, nearly smooth, flattened, 1.4-1.7 mm. in diameter, wedge shaped, nearly circular with a small notch on the thin edge. Naturalized from Europe. [Illustration: Fig. 131.] =Whorled Mallow.= _Malva verticillata._ L. Flowers white; cluster of 10-12 fruits flattened, circular with depression on each side, carpel circular, wedge-shaped, about three rows of irregular shallow pits on the wide edge, radiating ridges on each flat side; seeds light brown, nearly smooth, flattened, wedge-shaped, ovate or nearly circular, 1.5-1.7 mm. long, with a small notch on the thin edge. Introduced from the west. [Illustration: Fig. 132.] =Prickly Sida.= _Sida spinosa_ L. Seed smooth, dull brown or reddish brown, having one side round and two sides flat or more or less concave, all edges obtuse while lying on one flat side, broadly ovoid, with one side nearly straight, scar at the larger end in the midst of a slight depression, 1.5-1.8 mm. long. Not yet common in Michigan. Introduced from the tropics. ST. JOHN'S-WORT FAMILY. HYPERICACEAE. [Illustration: Fig. 133.]