CLASSIFICATION OF ARCHICHLAMYDEAE 251 



Lythraceae with 340. The high character of this alliance is in- 

 dicated by the constantly perigynous and epigynous flowers, as 

 well as by the constantly cyclic stamens, and the tendency to 

 tetramerous flowers is strong. 



XXVI. UMBELLALES.* This includes the Araliaceae, 

 Umbelliferae, and Cornaceae, together containing about 2,660 

 species, about 2,100 of which belong to the Umbelliferae. The 

 series is clearly the ranking one among the Archichlamydeae on 

 account of its epigyny, cyclic stamens, reduced number of car- 

 pels, and mostly reduced sepals, the floral formula being the 

 same as that of the highest Sympetalae. The three families 

 constituting the alliance are very closely related, and the alliance 

 as a whole stands so stiffly apart from other Archichlamydeae 

 as to raise the question whether it does not really belong among 

 the higher Sympetalae. 



It will be noted that in a large sense, and with the excep- 

 tion of the last two alliances, the Archichlamydeae correspond 

 to the Spiral series among Monocotyledons, in which the cyclic 

 arrangement, although it frequently appears, is not fully estab- 

 lished in every set of floral members. In the same sense, there- 

 fore, the Myrtales, Umbellales, and Sympetalae, correspond to 

 the Cyclic series among Monocotyledons. 



* UMBELLIFLORAE of Engler. 



