26 BOTANICAL GAZETTE [JANUARY 
forms. We believe, for reasons previously given, that the type of 
flower found among the Magnoliaceae is primitive. 
The present investigation adds little toward the solution of 
the plexus of problems involved in the origin of angiosperms and 
the relative primitiveness of existing groups. An opportunity was 
offered, however, to determine whether such a study as the present 
one of a possibly primitive group of angiosperms might yield any 
results of either positive or negative value as a contribution to 
present theories; to suggest new points of view and especially to 
emphasize certain old ones; to review briefly some of the principal 
theories of the present day on the primitiveness and origin of 
monocotyledons and dicotyledons; and finally to criticize where 
it seemed this might be helpful in bringing about in the future 
reinforcement or correction either of earlier theories or of the views 
expressed in this paper. 
Summary 
t. In both Magnolia and Liriodendron the sporogenous tissue 
in the anther is differentiated early in the winter. Tetrads develop 
by the simultaneous method and the pollen grains when mature are 
binucleate in Magnolia, two-celled in Liriodendron. The tapetum 
originates from the sporogenous tissue. 
2. The x number of chromosomes in each species is 19. 
3. The ovules in both species are marginal, anatropous, and 
provided with two integuments. The megaspore mother cell in 
each species, by two successive divisions, produces 4 megaspores, 
of which the innermost is functional. The mature embryo sacs 
are of the ordinary 8-nucleate type and fertilization probably 
occurs as usual. a 
4. The endosperm of Magnolia is cellular from the beginning 
of its formation and is abundant in the mature seed, surrounding 
a small, typically dicotyledonous embryo. The first division in 
the development of the embryo is transverse, the second longi- 
tudinal to the long axis of the embryo sac. The embryo has 4 
well defined suspensor and no evidence of monocotyledony was 
found. 
5. The eal of Magnolia possesses three coats: an outer fleshy 
