MEDICAGO SATIVA 337 



with stomata on both surfaces. The cells of the upper epidermis 

 are somewhat papillate with sinuous radial walls. Stomata are 

 numerous in the lower epidermis. Westgate (34) has reported an 

 average of 191 per sq. mm. for ordinary alfalfa, 185 for M. falcata, 

 and III for variegated alfalfa; while Wilson (35) found consider- 

 ably over twice that number, reporting up to 700 per sq. mm. The 

 lower epidermis is similar to the upper except that there are greater 

 numbers of hairs produced, especially along the veins. These are 

 of two kinds, the more numerous type being a long (0.7 to 1.5 mm.) 

 unicellular hair which is somewhat curved and arises from a 

 small thick-walled, basal cell around which the epidermal cells 

 form a rosette pattern. The capitate hairs are scattered and 

 much less abundant, consisting of a stalk of two or three cells and 

 a terminal multicellular head. 



LITERATURE CITED 



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3. Brenchley, W. E., and Thornton, H. G., "The relation between the develop- 



ment, structure and functioning of the nodules on Vicia faba, as influenced 

 by the presence or absence of boron in the nutrient medium." Proc. Koy. 

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4. Brink, R. A., and Cooper, D. C, "The mechanism of pollination in alfalfa 



(Medicago sativa)." Am. Jour. Bot. zy 678-683, 1936. 



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production." Jour. Am. Soc. Agron. zz: 780-786, 193P. 

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Linn. Jour. Bot. 41: i-iii, 1911. 



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Can. Jour. Res. }: 3-50, 1930. 

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1911. 

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