388 MORPHOLOGY OF THE ANGIOSPERMS 



ranalian family Lactoridaceae. Like other families of the Ranales, it 

 possesses both primitive and advanced characters. Its solitary or paired 

 flowers are polygamomonoecious; its perianth, a whorl of three sepals; 

 its stamens, in two whorls of three stamens each; and its three carpels in 

 one whorl. The stamens (Fig. 49G) are primitive— laminar, with four 

 elongate, "somewhat remote" sporangia; the sporangia, abaxial and shown 

 in illusti-ations as apparently protiuding; the connective projects beyond 

 the anther sac. The pollen is in tetrads, monocolpate, but elaborately 

 sculptured. The carpels are folHcular, with several suspended, ana- 

 tropous ovules and a short, perhaps decurrent, stigmatic crest on the 

 ventral margin. In illustrations, the carpels appear to be open in Hower 

 and fruit. The embryo is small, in abundant endosperm. Anatomically, 

 the genus is insufficiently known, but the nodes are unilacunar, and 

 the vessels are reported to be simply perforate, the wood rays all 

 heterogeneous, and the fibers with bordered pits. 



The family is definitely ranalian in its free floral organs, primitive 

 stamens and carpels, and monocolpate pollen borne in tetrads. The 

 stamen, without differentiation of filament and anther, and the open 

 carpel are prominent primitive organs. The extent of protuberance of 

 the microsporangia cannot be determined from the published figures. 

 The abaxial position of the microsporangia on a laminar sporophyll 

 adds one more family to the small list of those that have this character. 

 If further study shows the carpel margins to be free and the stigmatic 

 crest two-lobed, the carpel would resemble that of Degeneria and 

 Drimi/s in primitiveness. 



The Lactoridaceae are apparently not closely related to any other 

 ranalian family. Though they resemble the Winteraceae in pollen char- 

 acters, especially the tetrad clustering, they differ in their much greater 

 specialization in flower structure — few organs in whorls — and in wood 

 with vessels. They resemble the Piperaceae in their simplified flowers 

 but, in many characters, are far less reduced. They seem to be one of 

 the isolated families in the Ranales, with closer resemblances to the 

 Winteraceae than to other families. 



Magnoliaceae 



The Magnoliaceae, best known of woody ranalian families because 

 of the large size of its flowers and its prominence in cultivation, have 

 frequently been considered the most primitive family in the Ranales, 

 and, in some phylogenetic classifications, the most primitive among 

 angiosperms. The family has long included several genera of doubtful 

 affinities. But on the basis of recent broad morphological studies, several 

 of these genera have been excluded — lllicium, Schisandra, Tetracentron, 

 Euptelea, Cercidiphijllum; so circumscribed, the family seems to form 



