442 The Ohio Naturalist. [Vol. Ill, No. 8, 



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Bot. Gaz., 31 : 339-346. 1901. 



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Bot. Studies. 2 : 643-655. 1901. 



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Sven.ska Vetenskaps." Akadeniien Handlingar. Bandet 36 : No. 

 5. 1902. 



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Gaz., 21 : 123-132. 1896. 



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EXPLANATION OF FIGURES. 



For the drawings, a Leitz stand and a Bausch and Lonib camera lucida 

 were used. For Figs. 7 and 16, 'a No. 2 Leitz ocular and No. 7 Leitz objective 

 were used ; for Fig. 9, a No. 8 Leitz ocular and No. 3 Leitz objective ; for 

 Fig. 17, a No. 2 Leitz ocular and ye Baucli and Lomb objective; for the 

 others a No. 6 Zeiss ocular and a No. 7 Leitz objective were used. The 

 magnifications given are those of the original drawings, which in the ]:)late 

 are reduced to -/$ of their diameters. 



Archesporial cell, x 950. 



Sporoc^'te and tapetal cell, x 950. 



Megasporocyte and two tapetal cells, x 950. 



Three megasporas and two tapetal cells, x 950. 



Four megaspores and two tapetal cells, x 950. 



Two-celled embryo-sac with remains of megaspores. x 950. 



Eight-celled embryo-sac showing the egg apparatus, conjuga- 

 tion of polar nuclei, and antepodals. x 630. 



Large lower endosperm nucleus and antipodals. x 950. 



Staminate flowers showing pollen-sacs and microsporocytes. 



X 230. 

 Pollen grains, x 950. 



Three-celled enibr3-o and persistent synergid. x 950. 

 Five-celled embryo, x 950. 

 Nine-celled embryo, x 950. 

 Seventeen-celled embryo, x 950. 

 Older em])r3-o showing derniatogen. x 950. 

 Embryo .showing origin of cotyledon (c), plumule (?'), radicle 



{d,e,/). X630. ' 

 Fig. 17. Nearly mature embryo showing growing point, cotyledon and 



radicle, x 450. 



