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The taxonomy of Linaria dalmatica (L.) Mill. is discussed and a lectotype is selected, viz plant-number XII.10, Linaria latifolia Dalmatica, magno flore Bauh., in the Joachim Burser herbarium, which is preserved in Uppsala. A comprehensive description of the species is given. Two varieties are included: var. dalmatica, native from Yugoslavia to Iran, and var. macedonica (Griseb.) Vandas, indigenous to the mountains of southern Yugoslavia. Photographs of the type specimens of each are presented. L. grandiflora Desf. is shown to be a synonym of var. dalmatica, and Vandas is the correct authority for var. macedonica. Var. macedonica probably has never been cultivated but var. dalmatica was under cultivation at least as early as 1594 in Europe. It is now cultivated in Asia and North America as well as in Europe. Although probably introduced into North America by 1894, the earliest voucher specimen is dated 1920. Presently growing in 15 states in the U.S.A. and six provinces in Canada, var. dalmatica has escaped from cultivation and has spread as a weed in very diverse habitats, especially in coarse-textured soils west of the 100th meridian.

pressed by S. arvensis. S. arvensis at 190

Summary. Amaranthus retroflexus, Chenopodium album, Ambrosia artemisiifolia, Setaria glauca, S. viridis and Echinochloa crusgalli were the most widespread and abundant of the 103 weed species found in eighty‐eight fields of tomatoes (Lycopersicon esculentum) and sweet corn (Zea mays) surveyed in Prince Edward County and in Essex and Kent Counties during 1960 and 1961. None of the important weeds in either crop occurred exclusively in that crop. Differences in weed floras were greater between regions than between crops. Abutilon theophrasti, Euphorbia maculata, Apocynum cannabinum var. suksdorfii and Physalis virginiana var. subglabrata, important weeds in both crops in Essex and Kent, were not found in any surveyed field in Prince Edward County. Average numbers of weed species per field were 15.7 in Prince Edward County and 12.9 in Essex and Kent. Small dense infestations of Fumaria officinalis and Salvia reflexa, rare weeds in Canada, were discovered in Prince Edward County. Mauvaises herbes des cultures de tomates et du maïs dans deux régions de l'Ontario

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