Trees of the Northern United States 133 



35. Seed without wings or hairs. 39. 



36. Seed with a tu.ft of hairs, capsule small. 37. 



36. Seed with wings, the wings sometimes with a fringe of 



long hairs. 38. 



37. Capsule with a little cup at the base. Populus. (64). 



37. No cup at the base of the capsule but 1 or 2 little 



glands may be present. Salix. (65). 



38. Capsule ver}^ long, wings of seed with a fringe of 



hairs. Catalpa. (77). 



38. Capsule short, wing of seed without hairs. 



Paulownia. (76). 



39. Seeds ver}- large, 4-2 in. in diameter. 40. 



39. Seeds much less than I in. in diameter. 41. 



40. Seed smooth with a large light spot at one end, with- 



out ridges or angles. Aesculus. (40). 



40. Seed with two or more vertical ridges, without a 



special light spot — a nut in an enclosing husk which 

 may be mistaken for a capsule. Hicoria. (61). 

 41 Seeds with a fleshy, scarlet aril, capsule lobed. 



Euonymus. (35). 



41. Seeds without an aril. 42. 



42. Seeds 1 or 2, capsule not bladdery. 43. 



42. Seeds several to many. 44. 



43. Capsules small without a cup at the base. 



Zanthoxylum. (17) 

 43. Capsule woody, h in. long, with prominent cup at 

 the base; seeds 2, oblong. Hamamelis. (45). 



43. Capsule splitting tardily, with the prominent calyx 



persistent at the tip. Cephalanthus. (82). 



44. Capsule triocular, large, bladdery. 45. 



44. Capsule with 5 — many cavities, small. 46. 



45. Capsule 3-lobed at the tip, with 3 styles, usually widest 



at the middle ror toward the outer end. 



Staphylea. (37). 



45. Capsule with a long, acute tip, with a single style, 



widest below the middle. Koelreuteria. (39). 



46. Capsules mostly woody, oblong, puberulent ; in corym- 



bose or umbellate clusters. Rhododendron. (66). 



46. Capsules depressed-globose. somewhat 5-lolied ; in 



corymbose or umbellate clusters. Kalmia. (67). 



