27(26). Fruit a capsule terminated by 2 prominent curved and incurved beaks, 

 1-3 dm. long 120. Martyniaceae, p. 1508 



27. Fruit not as above (28) 



28(27). Herbs with opposite leaves and the odor of wet wool (or a wet dog); 

 stamens 3 (rarely 2); flowers minute, white, in terminal dichasia 

 or compound cymes; calyx minute, annular, involute (often un- 

 rolling after anthesis) or with minute teeth; fruit a 1 -seeded achene- 

 like structure 126. Valerianaceae, p. 1562 



28. Plants not as above, usually with 2, 4 or 5 stamens and with the calyx 



usually better-developed (29) 



29(28). Herbs usually with linear leaves; fruit a capsule, more or less com- 

 pletely 10-celled, at maturity splitting into 5 or 10 parts which fall 

 away separately 76. Linaceae, p. 1073 



29. Herbs, shrubs or trees; fruit not as in flax (30) 



30(29). Leaves alternate and stipulate (the stipules sometimes small, deciduous) 

 (31) 



30. Leaves alternate, opposite or whorled, either not having stipules or if with 



stipules then opposite (32) 



31(30). Fruit subglobose, drupaceous (with several stones), reddish to yellow- 

 ish or black, usually 5-10 mm. thick 82. Aquifoliaceae, p. 1097 



31. Fruit a capsule or schizocarp 88. Sterculiaceae, p. 1125 



32(30). Leaves opposite or whorled and with stipules, the evidence of stipules 

 sometimes reduced to mere stipular lines or membranes at the sides 

 of the node (here may also be sought certain Rubiaceae whose 

 essential epigyny has been overlooked).... 107. Loganiaceae, p. 1308 



32. Leaves opposite or alternate, without the slightest evidence of stipules (33) 



33(32). Stamens 2 or 4, fewer than the 5 corolla lobes (the number of corolla 

 lobes may be obscure in highly zygomorphic corollas) (34) 



33. Stamens 5 in flowers with 5 corolla lobes or 4 in flowers with 4 corolla lobes 



(this usually easily ascertained) (40) 



34(33). Fruit not capsular, either schizocarpous and breaking into 1-seeded 

 achenelike parts or else drupaceous; leaves always opposite (35) 



34. Fruit a capsule or a samara; leaves opposite or alternate (37) 



35(34). Flowers strongly zygomorphic; style usually manifestly bifurcate near 

 the apex (lower branches usually shorter than the upper); fruit 

 a schizocarp 117. Lahiatae, p. 1407 



35. Flowers usually only slightly if at all zygomorphic; style usually micro- 



scopically if at all bifurcate at apex; fruit schizocarpous or dru- 

 paceous (36) 



36(35). Fruit a 1-seeded drupe 106. Oleaceae, p. 1301 



36. Fruit a schizocarp or a druf>e with 2 or more seeds 



116. Verbenaceae, p. 1393 



37(34). Seeds minute, attached to a free central placenta in the 1 -celled ovary; 



fruit a 2- or 4-valved capsule; small herbs 



121. Lentihulariaceae, p. 1510 



37. Seeds attached to axile or nearly axile placentas in the 2-celled ovary; fruit 



a capsule or samara (38) 



26 



