IOWA ACADEMY OF SCIENCES. 171 



Fink, Proc. Iowa Acad, of Sciences, Vol. 4, p. 101; Fitz- 

 patrick, Proc. Iowa Acad, of Sciences, Vol. 5, p. 127, and p. 

 163; Vol. 6, p. 196; Cameron, Iowa Geol. Sur., Vol. 8, p. 198; 

 Macbride, Iowa Geol. Sur., Vol. 4, p. 119; Vol. 7, p. 107; 

 Vol. 9, p. 152; Vol. 10, p. 647; Reppert, Iowa Geol. Sur., Vol. 

 9, p. 386; Britton and Brown, Ills. Flora, Vol. 1, p. 509. 



Betula lutea Mx. f. Arb. Am., 2: 152, PI. 5, 1812. 



This species is reported by Barnes, Reppert, and Mille" 

 from Scott and Muscatine counties in Proc. Davenport 

 Academy of Natural Sciences, Vol. 8, p. 256. They state 

 that the species is common along rivers. They mention 

 no other birch, and as Mr. Reppert had only shortly before 

 reported Betula nigra L. as common along streams in Mus- 

 catine county in his article. Forest Trees and Shrubs in 

 Muscatine County, published in volume 9 of the Iowa 

 Geological Survey, there seems a probable error. Britton 

 and Brown give the range of this species as Newfound- 

 land to Manitoba, south to North Carolina and Tennessee, 

 mainly in the Alleghanies. In all probability Betula nigra 

 L. was the species considered and that Betula lutea Mx. f. 

 does not occur in Iowa. 



Betula papyrifera Marsh. Arb. Am., 19, 1785. Paper or 

 Canoe Birch. A tree, usually thirty to sixty feet high, 

 usually one to two feet in diameter, with chalky white 

 bark separable into very thin sheets, and brownish twigs; 

 leaves ovate, acuminate, unequally doubly serrate, slender 

 petioled, base obtuse to subcordate, glabrous and green 

 above, glandular and somewhat pubescent beneath. 



This species is frequent in rich woods, along streams, in 

 northeastern Iowa. The wood is light, strong, tough, 

 close-grained; mostly used for fuel in Iowa; may be used 

 in the manufacture of spools, shoe-lasts, pegs, turnery, 

 etc. The tough bark separating easily into thin layers is 

 very durable and impervious to water, and has been used 

 by the Indians in the manufacture of canoes and tents. 



Our specimens are from Winneshiek county. We have 

 observed the species in Allamakee, Clayton, and Dubuque 

 counties. The State University herbarium has specimens 

 from Delaware county. Professor Fink reports the species 



