78 THE ROYAL SOCIETY OF. CANADA 



Hordeum jubalum L. 

 Rumex sp. 



Axyris amarantoides L. 

 Amaranthus retroflexus L. 



" graecizans L. 



Agrostemma Githago L. 

 Silène noctiflora L. 

 Saponaria Vaccaria L. 

 Cleome serrulata Pursh. 

 Rosa pratincola Greene. 

 • Trifolium hybridum L. 

 Astragalus caryocarpus Ker. 

 Hedysarum boréale Nutt. 

 Oenothera biennis L. 

 Gaura coccinea Pursh. 

 Gilia linearis (Nutt.) Gray. 

 Lappula echinata Gilibert. 

 Agastache Foeniculum (Pursh) Ktze. 

 Dracocephalum parviflorum Nutt. 

 Stachys palustris L. 

 Plantago major L. 



" Rugelii Dene. 

 Symphoricarpos occidentalis Hook. 

 Grindelia squarrosa (Pursh) Dunal. 

 Iva axillaris Pursh. 

 Iva xanthifolia Nutt. 

 Ambrosia trifida L. 

 Rudbeckia laciniata L, 

 Helianthus scaberrimus Ell. 



" Maximiliani Schrad. 

 Coreopsis tinctoria Nutt. 

 Achillea Millefolium L. 

 Artemisia biennis Willd. 

 Cirsium undulatum (Nutt.) Spreng. 

 Cirsium arvense (L.) Scop. 

 Sonchus arvensis L. 

 Lactuca pulchella (Pursh) DC. 



Sclerotia of Claviceps purpurea (Fr.) Tul. are also commonly 

 found in Western grain and sometimes occur in elevator screenings. 



Commercial Separations of Screenings 



The material removed by the elevator cleaners in bringing the 

 grain up to the standard for the grade to which its quality entitles it, 

 may be divided roughly into two portions. 



(1) The smaller weed seeds removed by means of a zinc sieve 

 containing perforations 1/14 inch in diameter. 



(2) Material too large to pass through the 1/14 inch sieve. 



