MICHIGAN ACADEMY OF SCIENCE. 35 



12. Two seeds in the fruit of cockle bur are so placed that one grows the 

 first year, and the other remains dormant till the second year. 



13. Some have creeping rootstocks or tubers. (Quack grass, nut-grass). . 



14. Some weeds defend themselves with forks and l^a^'onets. (Thistles). 



15. Stout rooted plants are skipped by the cultivator. (Dock). 



16. Most of them are disagreeal^le in taste or odor, so that domestic animals 

 leave them to occuin- the ground and multiply. (Jamestown weed, stink 

 grass, milkweed). 



I have recentl}' examined 122 samples of clover seeds, which contained 

 51 kinds of weed seeds; 9 samples of this number contained no weed seeds. 



Seventy samples of clover seed contained seeds of Chaetochloa viridis 

 (green foxtail). 



Sixty samples contained Plontago lanceolata (buckhorn). 



Fifty-eight samples contained Plantago Rugelii (Rugel's plantain). 



Fifty samples contained Rumex crispus (narrow-leaved dock). 



Forty-six samples contained Rumex acetosella (sheep sorrel). 



Thirty-six samples contained Polygonum Persicaria (lady's thumb). 



Thirty samples contained Chenopodium album (lamb's tjuarters). 



Twenty-three samples contained Plantago major (one of the broad-leaved 

 plantains). 



Twenty-three samples contained Panicum Crus-galli (barnyard grass). 



Twent3'-one samples contained Ambrosia artemisiaefolia (common rag- 

 weed). 



Seventeen samples contained Panicum capillare (hair grass). 



Sixteen samples contained Panicum sanguinale (crab grass). 



Fifteen samples contained Potentilla Monspeliensis. 



Fourteen samples contained Amaranthus retroflexus (our most common 

 rough pigweed). 



Thirteen samples contained Lepidium Virginicum (one of the pepper 

 grasses). 



Nine samples contained Chaetochloa glauca (yellow foxtail). 



Nine samples contained Alsine media (our most common chickweed). 



Eight samples contained Nepeta Cataria (catmint). 



Seven samples contained Lepidium apetalum (a small pepper grass). 



Six samples contained Prunella vulgaris (self heal). 



Five samples contained Cerastium vulgatum (mouse-ear chickweed). 



Four samples contained Bi-omus secalinus (common chess). 



Three samples contained Rumex obtusifolius (broad-leaved dock). 



Three samples contained Anthemis Cotida (Mayweed). 



Three samples contained Onagra biennis (evening primi-o.se). 



Three samples contained Daucus carrota (wild carrot). 



Two samples contained Panicum lineare (narrow-leaved panicum). 



Two samples contained Lithospermum arvense (red root). 



Two samples contained Lolium perenne (perennial rye grass). 



Two samples contained purslane. 



Two samples contained Cichorium Intybus (chickory). 



Two samples contained Brassica nigra (black mustard). 



Two samples contained Carduus arvensis (Canada thistle). 



Two samples contained Cuscuta arvensis (dodder). 



Two samples contained Verbena urticifolia (nettled-leaved verbena). 



One sample contained Medicago lupidina (black medick). 



One sample contained Ranunculus bulbosa (bulbous crowfoot). 



One sample contained Ranunculus repens (creeping crowfoot). 



