246 MORPHOLOGY OF ANGIOSPERMS 



alliances. It follows that the subsequent alliances will touch the 

 Ranales in various ways, the latter representing a plexus out of 

 which various divergent lines have become distinct. This con- 

 ception of the genetic position of Ranales among Archichlamy- 

 deae has brought to them the attention of morphologists, and 

 the results thus far have more than justified their investigation. 



XVI. RHOEDALES. This includes Papaveraceae, Cruci- 

 ferae, Tovariaceae, Capparidaceae, Resedaceae, and Moringa- 

 ceae, together containing about 2,615 species, the large families 

 being Cruciferae with 1,860 species, Capparidaceae with 425, 

 and Papaveraceae with 280. There seems to be no question 

 that this alliance is closely related to the Ranales. The connec- 

 tion seems to be through the Papaveraceae, which exhibit struc- 

 tures resembling those of Xymphaeaceae ; while the transition 

 from Papaveraceae to Cruciferae through the Fumaria forms 

 is plain, and the affinity of Cruciferae and Capparidaceae is 

 unquestioned. 



XVII. SAKRACENIALES. This includes Sarraceniaceae, 

 Nepenthaceae, and Droseraceae, together containing 145 spe- 

 cies, nearly 100 of which belong to the Droseraceae. The 

 alliance is evidently parallel with Rhoedales, and both are cer- 

 tainly related to the ^Nymphaeaceae-region of the Ranales. In 

 fact, the Xymphaeaceae, Papaveraceae, and Sarraceniales have 

 many things in common in the arrangement of floral members 

 and the spirocyclic character of the flowers. The distinctive 

 character of Sarraceniales as compared with Rhoedales is the 

 prevalence in the former of central placentation. 



XVIII. ROSALES. This includes Podostemonaceae, Hy- 

 drostachyaceae, Crassulaceae, Cephalotaceae, Saxifragaceae, 

 Pittosporaceae, Brunelliaceae, Cunoniaceae, Myrothamnaceae, 

 Bruniaceae, Hamamelidaceae, Platanaceae, Crossosomataceae, 

 Rosaceae, Connaraceae, and Leguminosae, together containing 

 about 14,270 species, the large families being Leguminosae with 

 over 11,000 species, Rosaceae with 1,525, Saxifragaceae with 

 630, and Crassulaceae with 490. Since this alliance contains 

 by far the greatest family of Archichlamydeae, in fact, with a 

 single exception, the greatest family of Angiosperms, it may 

 be regarded as the most representative and dominant alliance. 



The beginnings of this great alliance, with apocarpy, hypo- 

 gyny, and indefinite repetition of certain floral members, have 



