106 MISSOURI BOTANICAL GARDEN. 



EXPLANATION OF PLATES. 



All of the illustrations were drawn by Miss Grace E 

 Johnson, under the supervision of the author. 



THE SUGAR MAPLES. 



Plate 4. Acer saccharum, typical form, natural size, with winter twig, 



X 3. 



Plate 5. 



natural 



specimen), with winter twig, X 3 (from a Missouri specimen). 



Plate 6. — A. saccharum var. barbatum, natural size (one of the originals 

 of A. Bugeliiy from Knoxville, Tenn.,— the isolated fruit and bud speci- 

 men from Rugel's Dandridge material), with bud characters, X 3. 



Plate 7. — Am saccharum var. nigrum* natural size ; with winter twig, X 3. 



Plate 8. — A. Floridanum, natural size (from Curtiss' Chattahooche 



material). 



Plate 9.— A. Floridanum, natural size (from Vasey's Chattahooche 



specimens), with bud characters, X 3 (from Letterman's Sodus material) . 



Plate 10.— A. Floridanum. natural size (from Mohr's Quitman 



specimens). 

 Plate 11.— A. Floridanum var. acuminatum, natural size (from Small 



and Heller's No. 381), with bud characters, X 3. 



Plate 12.— A. grandidentatum, natural size (from Jones' material). 



Plate 13.— A. grandidentatum, natural size (a Mexican form, from 

 Mearns' material). 



WINTER CHARACTERS OP MAPLES. 



(Twigs natural size : details X 3 ) . 

 Plate 14.— 1 to 3, A. Pennsylvanicum ; 4 to 6, A. glabrum; 7 to 9, A. 



spicatum; 10 to 13, A. circinatum. 



Plate 15.— 14 to 16, A. macrophyllum ; 17 to 18, A. saccharinum (dasy- 

 carpum); 19 to 23, A. rubrum; 24 to 26, A. rubrum var. DrummondiL 



Plate 16.— 27 to 29, A. grandidentatum; 30 to 32, A. saccharum; 33 to 

 34, A. saccharum var. barbatum; 35 to 86, A. saccharum var. nigrum; 



37 to 38, A. Floridanum. 



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