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HUMBLEBEES. 



1892. In Agr. Gaz. N. S. Wales, v. 3, pt. 1, p. 78. 



HUMBLEBEES. 



1897. In Agr. Gaz. N. S. Wales, v. 8, pt. 5, p. 353. 

 Hunt, T. F. 

 1907. The Forage and Fiber Crops in America. New York, 413 p., illus. 



1909. Pollination of clover. In Wallace's Farmer, v. 34, no. 43, p. 1347. 

 Kerner, A. J. 

 1895. The Natural History of Plants ... [tr.] from the German ... v. 2. London. 



KlRCHXER, OsKAR. 



1905. tiber die Wirkung der Selbstbestaubung bei den Papilionaceen. In 



Naturw. Ztschr. Land- u. Forstw., Jahrg. 3, Heft 1. p. 1-16. 

 Kntjth, P. E. O. W. 

 1906-08. Handbook of Flower Pollination ... v. 1-2. Oxford. 



LlNDHARD, E. 



1911. Om B,0dkl0verens BestoVning og de Humlebiarter, som herved er virk- 

 somme. In Tidsskr. Landbr. Planteavl, Bd. 18, Haefte 5, p. 719-737, 

 illus. 



McAlpine, A. N. 



1898. Production of new types of forage plants — clovers and grasses. In Trans. 

 Highland and Agr. Soc. Scot., s. 5, v. 10, p. 135-158, fig. 33-39. 



Martin, J. N. 



1913. The physiology of the pollen of Trifolium pratense. In Bot. Gaz., v. 56, 

 no. 2, p. 112-126, 1 fig. 



1914. Comparative morphology of some Leguminosse. In Bot. Gaz., v. 58, 

 no. 2, p. 154-167, pi. 8-11. 



Martinet, G. 



1903. Etudes et essais de plantes fourrageres. In Ann. Agr. Suisse, arm. 4, p. 

 160-169, illus. 



Meehan, Thomas. 



1876. Fertilization of flowers by insect agency. Abstract with discussion by 

 Asa Gray and others. In Proc. Acad. Nat. Sci. Phila., 1876, p. 108-112. 



Muller, Hermann. 



1883. The Fertilization of Flowers. London, 669 p., illus. 



Pammel, Edna C, and Clark, Clarissa. 



1911. Studies in variation of red clover. In Proc. Iowa Acad Sci., 1911, p. 47-53, 

 4 pi. 



Pammel, L. H. 



1903. Ecology. Carroll, Iowa, 360 p., illus., pi. 



and King, Charlotte M. 



1911. Pollination of clover. In Proc. Iowa Acad. Sci., 1911, p. 35-45. illus. 



Robertson, Charles. 



1892. Flowers and insects. In Bot. Gaz., v. 17, no. <i. p. ] 7:1-170. 



Schneck, Jacob. 



1891. Further notes on the mutilation of flowers by insects, In Lot. Gaz., v, 



16. no. 11. p. 312-313. 

 Seeding of red clover. 

 1895. In Agr. Gaz. N. S. Wales, v. 6. pt. 6, p. 439. 



