EXPERIMENT STATION BULLETINS. 183 



Fig. 7. — Red clover, the two uppermost enclosed in the little pod. 



Fig. 8. — Alsil:e clover. 



Fig. 9. — Crimson clover. 



Fig. 10.— Alfalfa. 



Fig. 11. — Clover dodder, love vine, (Cuscuta epithymum). Surface dull or minutely scurfy; color 

 greenish gray, yellovi'isli or brownish; often irregularly flattened, with a minute scar at one 

 end. 



Fig. 12. — Field dodder (Cuscuta arvensis) shaped much like the preceding but larger; surface dull 

 or slightly scurfy; color yellowish, reddish or brownish. The color of these seeds so closely 

 resembles that of alfalfa as to make their separation exceedingly difficult. The surest way 

 to identify suspected dodder seeds is to soften them in water and carefully open them with 

 needles niounted in handles. The embryo plant of the dodder seeds is slender and coikd 

 up inside of a floury material, while the embryo of a clover or alfalfa seed much resembles 

 that of a bean. 



Fig. 1.3. — Narrow-leaved plantain, Rib grass, Buckhorn, plantain. (Plantago lanceolata). Some- 

 what boat-shaped, with a small scar on the grooved side: surface smooth, shining; color 

 light brown, often with a lighter stripe along the convex side. 



Fig. 14. — Broad-leaved plantain. (Plantago Major.) Shape angular, flattened; surface minutely 

 rough and dull; color brown or brownish with a minute wdiitish scar on one side. 



Fig. 15. — Rugel's plantain. (Plantago Rugelii.) Much like the above but somewhat larger and 

 darker in color, being almost black with a conspicuous light scar on one side. 



Fig. 16. — Curled dock. (Rumex crispus.) With the calyx removed these resemble small kernels 

 of buckwheat, being triangular and with a smooth, polished surface; color reddish brown. 



Fig. 17. — Canada thistle. (Carduus arvensis.) Shape somewhat angled lengthwise and often slightly 

 curved with a small scar at smaller end, larger end cup-like with a small central projection; 

 surface smooth but not polislied; color light to dark brown. 



Fig. 18. — Bull thistle. (Carduus lanceolatus.) These are much like the preceding but slightly 

 larger and more often yellowish or light grayish in color. 



Fig. 19. — Chess. (Bromus secalinus.) These appear slightly like small kernels of oat, but some- 

 times possess a short spine or awn. The chaff encloses a reddish grain which is folded 

 lengthwise and has a dull surface. 



Fig. 20. — Russian thistle. (Salsola Tragus.) These are often found enveloped with a dry calyx 

 of a light gray color. When this is rubbed off the seed (fruit) resembles somewhat in form 

 a chocolate drop with a concave base, in the center of which is a minute point. Surface 

 dull, color grayish brown; embryo plant coiled in the seed. 



Fig. 21. — Green foxtail. (Chaetochloa viridis.) The grains are usually partly enveloped with the thin, 

 membranous cliafT which is yellowish or greenish gray; the enclosed grain is brownisli, mottled 

 with a darker brown; surface dull except two narrow polished stripes along the edges of the 

 flattened side. 



Fig. 22. — Yellow foxtail. Pigeon Grass. (Chaetochloa glauca.) These are larger and lighter colored 

 than the preceding, the chaff being greenish while the grain is mostly yellowish or brownish 

 and transversely wrinkled. 



Fig. 23. — Redroot, Wheat-thief. (Lithospermum arvense.) Shape somewhat conical with a con- 

 vex base; surface roughened with irregular ridges and tubercles; color grayish, with the con- 

 vex base nearly black. 



Fig. 24. — Wild carrot. (Daucus carota.) Shape flattened with one side convex and bearing four 

 rows of liglit colored spreading spines; color browni,sh. As found in clover seed the spines 

 have in most cases disappeared, the convex side showing four light colored lines lengthwise. 



Fig. 25. — Peppergrass. (Lepidium virginicum.) Shape much flattened, with a thin, narrow margin 

 and a groove extending part of its length on each side; surface dull; color light brownish 

 red. 



Fig. 26. — Wild turnip. (Brassica campestris.) Shape nearly spherical; surface smooth but dull; 

 color purplish brown or blackish with a very small light scar. 



Fig. 27. — Lamb's quarters pigweed. (Chenopodium album.) These are at first enclosed in a dry 

 closely fitting envelope which breaks away in places exposing the smooth, shiny, black seed 

 which is flat tened-con vex. 



Fig. 28. — Corn cockle. (Agrostemma githago.) These appear to be folded upon themselves; sur- 

 face rough with points arranged in rows; color brownish black. 



Fig. 29. — Evening catchfly. CSilene noctiflora.) These are much smaller than the preceding but 

 otherwise resemble them somewhat in shape and surface; color grayish brown. 



Fig. 30. — Ragweed. (Ambrosia artemisaefolio.) These are somewhat egg-shaped with a pointed 

 projection surrounded with a crown of several tooth-like points at the large end; "surface 

 dull and slightly ridged; color yellowish, grayish or brown, often somewhat mottled. 



