34 EXPERIMENT STATION. [Jan. 



bean. Its color varies from brown to black, and to the eye the 

 surface appears to be covered with small depressions of a roughly 

 pentagonal form, which give a wrinkled appearance to the seed. 

 This troublesome weed seed is, however, very seldom found. 



Rib Grass {Flantago lanceolaia, L.). — The seeds of this as 

 well as of other varieties of plantain are very often found in 

 grass seeds as well as in commercial feed stuffs, but each is so 

 different in appearance that it is easy to recognize them, either 

 with the naked eye or by the help of a hand lens. The seed of 

 Plantago lanceolaia is shaped very much like a blunt, double- 

 ended canoe, the convex side being shiny brown to black in color, 

 and the concave side a little lighter as a rule. The seeds are 

 about Me of an inch in length. There is in this variety no trans- 

 verse line crossing the back of the seed. 



Bkacted Plantain" {Plantago aristata, L.). — The seeds of 

 this variety of plantain are somewhat larger than those of the 

 rib grass but are of much the same shape, i.e., canoe shaped, but 

 are flatter. They vary in length from %2 to /^ of an inch, and 

 on the concave side are distinctly marked with a concentric ring 

 of light color enclosing an inner portion of a grayish white 

 color. They are brown on the convex side, and this side is 

 marked with a slight transverse depression, which is usually 

 visible to the naked eye and which is easily distinguished under 

 the hand lens. 



Bindweed, Wild Buckwheat {Polygonum convolvulus, L.). 

 — This weed seed is probably the one that occurs most fre- 

 quently as an adulterant and impurity in feeds and grass seeds. 

 It is shaped like the seed of buckwheat, but is smaller, never 

 being over % of an inch long. In color the seed is jet black or 

 sometimes brownish black. Under the lens the seed appears to 

 be covered with very minute projections, giving it a roughened 

 apjDearance. 



Lady's Thumb, Smaetweed {Polygonum persicaria, L.). — 

 This seed belongs to the same family as the one just described, 

 and is often found as an impurity in grass seeds, etc. In shape 

 it is much like a flattened buckwheat seed, having two distinct 

 sides instead of three. In color it varies from dark, glossy 

 brown to black, and the surface is very smooth. The seed is 



