310 C;UCURBITALES. [Diclinous Exogens. 



Alliance XXIV. CUCUBBITALES.—Tee Cucurbital Alliance. 



Diagnosis. — Diclinous Exogens, with monodicJilamydeous flowers, inferioi' fruit, parietal 

 placentcB and embryo without a trace of albumen. 



The plants of tliis Alliance differ from all others in their dicUnous flowers, combined 

 \vith an inferior ovary, whose placentee are more or less manifestly parietal. They ap- 

 proach Menispermads in then' scrambling habit, and Passionworts in their placentation. 

 In the greater part the stigmas are horseshoe-shaped. They differ from Papayals in 

 their inferior ovary and exalbuminous seeds, and from the scrambling genera of Euphor- 

 bials in the same circumstances. 



Natural Orders of Cucurbitals. 



Fruit pulpy. Placentce strictly parietal. Monopetalous .... 105. Cucurbitace^. 



Fruit dry. Placentae strictly parietal. Apetalous 106. Datiscace^. 



Fruit dry. Placentce projecting and meeting in the axis. Mono-\ .^„ t5 _„ 



dichlamydeous J '• ^ nia 



