=Common Chickweed.= _Stellaria media_ (L.) Cyrill. _Alsine media_ L. Flowers white; seeds reddish yellow to dark brown, somewhat flattened, nearly circular, each side covered with 5-6 curved rows of tubercles, giving the appearance of having the two extremities bent together, about 1 mm. in diameter. Introduced from Europe, thriving in cool weather in shade. PURSLANE FAMILY. PORTULACACEAE. [Illustration: Fig. 72.] =Purslane. Pussley.= _Portulaca oleracea_ L. Flowers yellow, seeds jet-black, shining, flattened, wedge-shaped, having three rounded nearly equal sides, broadly oval or almost circular, often having a curved tooth or point on one side, with 3-4 curved rows of minute tubercles. Seed .5-.8 mm. in diameter. Naturalized from the southwest. Every gardener knows how difficult it is to exterminate this weed. CROWFOOT FAMILY. RANUNCULACEAE. [Illustration: Fig. 73.] =Small-flowered Crowfoot.= _Ranunculus abortivus_ L. Achene light brown to straw colored, 0.8-1.2 mm. in diameter, oblong, 0.3 mm. thick, when seen in cross sections, surface uneven with minute wrinkles, pits and dots flattened, broad oval to circular, three-sided, bearing the remains of a short curved style. Rich, low woods, not a common weed. [Illustration: Fig. 74.] =Bitter or Tall Buttercup.= _Ranunculus acris_ L. Achenes dull, dark brown, two-beaked, somewhat lens-shaped, 3-4 mm. long, one edge very slightly convex, the other prominently so, or somewhat semicircular in outline, hem-like margin, obscure. Introduced from Europe. Low land. [Illustration: Fig. 75.] =Bulbous Buttercup.= _Ranunculus bulbosus_ L. Achenes dull brown, nearly circular, diameter 3-4 mm.; beak short, turned to one side, surrounded by a narrow, hem-like margin. In June, many meadows of New England and New York are yellow with great numbers of flowers. Introduced from Europe. Upland; fortunately not yet common in this state. [Illustration: Fig. 76.] =Creeping Buttercup.= _Ranunculus repens_ L. Achenes plump, dull, light-brown, nearly circular, diameter 3-4 or more mm.; beak more or less hooked, hem-like margin conspicuous. This species usually seeds very sparingly, but when once introduced, it looses no time in spreading by creeping stems. Introduced from Europe. Moist land; a rapid spreader by runners. POPPY FAMILY. PAPAVERACEAE. [Illustration: Fig. 77.] =Celandine.= _Chelidonium majus_ L. Yellow sap, yellow flowers; seeds dark brown to almost black, ovoid, 1.2-1.5 mm. long, with 10-12 curved vertical rows of small square depressions on each side; projecting from one side a prominent white or cream-colored ridge, irregularly wrinkled when dry. Introduced from Europe. Persistent. MUSTARD FAMILY. CRUCIFERAE. [Illustration: Fig. 78.]