=Remarks.=--The trees are too small to be of much economic importance. It is 30 per cent stronger than white oak, and 46 per cent more elastic. These exceptional qualities were recognized by the Indians and it was used by them where wood of great strength and hardness was desired. Likewise the pioneer used it where he could for handles, wooden wedges, etc. Since it grows neither large nor fast, it is usually regarded as a weed tree in the woodland, and should be removed to give place to more valuable species. =Ostrya virginiàna= variety =glandulòsa= Spach. This is the name given to the form which has the twigs, petioles, peduncles and often the midrib and veins of the leaves beneath covered more or less with short erect, reddish, glandular hairs. It is found with the species, but is not so frequent. [Illustration: Plate 31. OSTRYA VIRGINIANA (Miller) K. Koch. Ironwood. (× 1/2.)] =3. BÉTULA.= The Birches. Trees and shrubs with bark tight, scaly or separating into very thin plates and peeling off transversely, whitish or dark colored; staminate catkins developing in autumn and dehiscing in early spring before or with the appearance of the leaves, pistillate catkins ovoid or cylindric; fruit a small winged flat seed, bearing at the apex the two persistent stigmas. Bark of twigs usually with a slight wintergreen flavor; leaves with 7-15, usually 9-11 pairs of prominent veins; rounded or slightly cordate at the base; fertile catkins generally 10 mm. or more in diameter. 1 B. lutea. Bark of twigs usually bitter, not wintergreen flavored; leaves with 4-11, usually 4-9 pairs of prominent veins, more or less obtusely angled at the base; fertile catkins generally less than 10 mm. in diameter (rarely 10 mm. or more, _B. nigra_). Bark of trunk chalky-white; fruiting aments drooping or spreading. Bark below base of lateral branches darkened-triangular in outline; leaves long acuminate and lustrous above; staminate catkins usually solitary. 2 B. populifolia. Bark below base of lateral branches not darkened; leaves ovate and not lustrous above; staminate catkins usually 2-3. 3 B. papyrifera. Bark of trunks dark; fruiting aments erect or nearly so. 4 B. nigra.