WEED SEEDS FOUND WITH BLUEGRASS SEEDS. 



35 



Anthemis cotula L. 



DOG FENNEL, MAYWEED. 



Seeds (akenes) cylindrical, broadly club-shaped, 1^2 mm. long, straight or 

 curved; surface dull and usually roughened by 

 many small tubercles more or less distinctly 

 arranged in ten rows, indistinctly few-tubercled 

 or nearly smooth, but commonly more or less 

 evidently ten-ribbed; base tipped by the rounded, 

 whitish scar; apex rounded or slightly pointed; 

 color varying from light to dark brown. ( Fig. 25. ) 



Found occasionally, but never abundantly, in 

 both American and European bluegrass seed. 



If 5 

 4 



b 



Fig. 25. — Seeds of dog ienneli Anthemis 

 eoUda): a, side views; 6, natural size 

 of seeds. 



Chenopodium album L. 



lamb's-quarters, pigweed. 



Seeds nearly circular, lens-shaped, with blunt edges, 1-1^ mm. in diameter, occur- 

 ring in commercial seeds as free seeds or as fruits, the seeds proper being invested by 



the thin pericarp; free seeds jet black, smooth 

 or nearly so, and highly polished; scar occu- 

 pying a curved groove extending from the cen- 

 ter to the edge of one face and usually evident 

 as a light-colored line; fruits only slightly 

 larger than the seeds, mostly gray or black and 

 dull; pericarp wall often broken away, expos- 

 ing theshining black surfaceoftheseed; again, 

 this wall and the seed coat are often broken, 

 exposing the yellowish or whitish embryo and 

 endosperm; embryo cylindrical, occupying 

 the border of the seed and surrounding the endosperm, its extremities almost meet- 

 ing, the tip of the caulicle occupying an extension of the seed coat at the edge beside 

 the scar. (Fig. 26.) 



Found chiefly in Kentucky bluegrass and Canada 

 bluegrass seeds, but not frequently and never abun- 

 dantly. 



Plantago lanceolata L. 



Fig. 26.— Seeds of lamb's-quarters (Chenopo- 

 dium album): o, various forms of seeds; 6, 

 natural size of seeds. 



b 



% 



Fig. 27. — Seeds of rib-grass {Plan- 

 tago lanceolata): a, front and back 

 views of seeds; b, natural size of 

 seeds. 



RIB-GRASS, BUCKHORN, ENGLISH PLANTAIN. 



Seeds oval-oblong, lf-3 mm. long, flattened, one 

 face convex, the other having a deep groove and 

 rounded, infolded edges which scarcely meet at one 

 end; surface smooth or slightly uneven, shining in 

 fresh seed, brown or somewhat amber-colored; scar 

 situated at the center of the grooved face; embryo straight, in the center of the 

 endosperm, usually evident through the somewhat transparent endosperm and seed 

 coat. When placed in water the seeds develop a coat of transparent mucilage. 

 (Fig. 27.) 



Small seeds are found to some extent in both American and European seed; more 

 commonly in Kentucky bluegrass than in Canada bluegrass seed. 



