84 



wide, densely pubescent on the back, or rarely glabrous on the back, 

 ciliate, glabrous or nearly so on the inside, commonly with a few brown 

 or black glands on the margin, commonly lobed to more than one- 

 third of their length, lobes ascending or divaricate, the lateral generally 

 the larger and almost as long as the narrower middle lobe; nuts divested 

 of the wings, slightly obovate, about 3 mm. long, wings about two-thirds 

 as wide as the nut and usually with a fringe of hairs at the blunt apex. 



Distribution. The distribution of this species is variously given 

 as from Newfoundland west to Manitoba and south in the Alleghenies 

 to Georgia. It is now definitely known that the species of Betula 

 hybridize which may account for the peculiar forms often encountered. 

 That there are geographic races or Mendelian segregates of this species 

 is evidenced by the different interpretations given this species by dif- 

 ferent authors. Betula alleghanensis Britton appears to be one of them. 

 The descriptive difference between Betula lenta and Betula lutea is not 

 clear, which has resulted in many authors crediting Betula lenta to 

 Indiana and the area west of Indiana. 



The preceding description does not agree with that of Betula tul< a 

 exactly, and has been drawn to cover the specimens at hand from In- 

 diana which the author has from Allen, Crawford, Lagrange, Lake, 

 Marshall, Porter and Steuben Counties. It has recently been reported 

 from White County byHeimlich. 1 He sa/ys: "Specimens were taken 

 from two trees about two miles south of Buffalo near the water's edge 

 of the river." The writer has visited this locality and found here, and 

 also on the island above the bridge a little farther down the river, 

 Betula nigra, but could not find Betula lutea. Since Heimlich did not 

 report Betula nigra, which unmistakably occurs here, I assume he has 

 confused the two species. It is very local in its distribution, and appears 

 to be confined to swamps, borders of lakes, and streams in the 

 extreme northern part of the State. It has not been seen south of the 

 northern end of the State, except a few small trees found clinging 

 to the walls of the cliffs of a ravine about one mile east of Taswell 

 in Crawford County. The walls of this ravine are about 25 meters 

 high; associated with it were a few trees of hemlock,- and on the top 

 of the cliffs, laurel ( Kalmia latifolia) . 



Large trees of this species in Indiana are usually from 4-6 dm. in 

 diameter and about 15 m. high. The number in any one station is 

 usually few, although there were formerly patches where it was plentiful. 

 Van Gorder 2 reports for Noble County Betula lenta which should be 

 transferred to this species, and he says: "There is a marsh of several 

 acres of birch in Section 15 of York Township." The largest area now 



iProc. Ind. Acad. Sci. 1917:443:1918. 

 2 Ind. Geol. Kept. 18:61:1894. 



