KEY TO THE FAMILIES 



Ovule with a ventral raphe; leaves mostly alter- 

 nate; blades lobed or compound. 



94. ARALIACEAE 633 

 Ovule with a dorsal raphe; leaves mostly op- 

 posite; blades entire or merely toothed. 



95. CORNACEAE 634 

 Fruit dry, a cremocarp; gynoecium 2-carpellary; 



stigmas terminal. 93. AMMIACEAE 606 



Styles united, or single. 



Ovary enclosed in or surpassed by the hypanthium or 



adnate to it. 

 Anthers opening by pores; fruit a berry. 



99. VACCINIACEAE 643 



Anthers opening by slits; fruit a capsule. 

 Ovary with parietal placentae. 



87. LOASACEAE 569 



Ovary with central or basal placentae. 



Hypanthium merely enclosing the ovary. 



90. LYTHRACEAE 582 

 Hypanthium adnate to the ovary. 



91. ONAGRACEAE 583 

 Ovary exceeding the hypanthium, the top free. 



58. HYDRANGIACEAE 392 

 Plants with tendrils; fruit a pepo; leaf-blades palmately veined. 



129. CUCUHBITACEAE 821 



II. Petals more or less united. 

 A. Ovary superior. 



1. Stamens free from, the corolla. 



Gynoecium of a single carpel; corolla papilionaceous. 



65. FABACEAE 454 



Gynoecium of several united carpels. 

 Filaments united. 



Stamens diadelphous. 51. FUMARIACEAE 319 



Stamens monadelphqus. 



Anther-sacs opening by slits; calyx and corolla regular. 



67. OXALIDACEAE 533 



Anther-sacs opening by pores; calyx and corolla very 



irregular. 73. POLYGALACEAE 540 



Filaments distinct. 



Corolla regular; anthers distinct. 



Herbaceous saprophytes, without green leaves. 



97. MONOTROPACEAE 638 



Herbs or shrubs with green leaves. 



Corolla of essentially distinct petals, i. e., united only 

 at the base; herbs with rootstocks. 



96. PYROLACEAE 635 

 Corolla of distinctly united petals; shrubs. 



98. ERICACEAE 639 

 Corolla irregular; one of the petals free; anthers united. 



69. BALSAMINACEAE 536 



2. Stamens partially adnate to the corolla. 



a. Stamens as many as the lobes of the corolla and opposite them, or 



twice as many or more; ovary 1-celled; placentae central or 

 basal. 100. PRIMULACEAE 646 



b. Stamens as many as the lobes of the corolla and alternate with 



them, or fewer. 



* Corolla not scarious, veiny; fruit various, but not a pyxis. 

 t Carpels distinct, except sometimes at the apex. 

 Styles united; stamens distinct or gynandrous. 



105. APOCYNACEAE 667 

 Styles distinct; stamens monadelphous. 



106. ASCLEPIADACEAE 669 



tt Carpels united. 



Ovary 1-celled, with central placentae. 



Corolla-lobes convolute or imbricated in the bud ; leaves 

 typically opposite and simple. 



103. GENTIANACEAE 657 



Corolla-lobes induplicate-valvate in the bud; leaves al- 

 ternate, in ours mostly basal and trifoliolate. 



104. MENYANTHACEAE 667 

 Ovary 2-3-celled, or falsely 4-celled, or if 1-celled with 



parietal placentae. 

 Stamens 2, opposite to each other; corolla regular. 



101. OLEACEAE 655 

 Stamens usually more than 2, if only 2 not opposite to 



each other and the corolla irregular. 

 Leaves with stipules or stipular lines. 



102. LOGANIACEAE 657 



