BoTANICAL GAZETTE 
FULY, 1893. 
the embryo-sac and embryo of Senecio aureus L. 
DAVID. M. MOTTIER.  j) 
; WITH PLATES XXVII—XXIX. 
We are made familiar with the structure and development 
the sac and the process of fertilization in the angio- 
ms by Dr. Eduard Strasburger in his masterly works, 
> permen und Gymnospermen,” ‘‘Zellbildung und Zell- 
sy and “Theorie der Zeugung.” Of the great number 
mts taken as illustrative types in only one of the Com- 
are the details of the development of the embryo-sac 
Y, Senecio vulgaris. The Composite, and, it 
the dicotyledons in general, present many diffi- 
‘the study of these processes. 
_ -vsetved, however, that Senecio aureus L., a ve 
mm native American species, is a very favorable object 
© study of the embryo-sac and the early stages in the 
ut of the embryo. Work upon this plant was 
hae chiefly for the purpose of comparison with that 
ce obtains in some of the lower dicotyledons and monocoty- 
see whether the process here differed in any way 
of the allied species, Senecio vulgaris, according to 
given by Strasburger. bs ata eek 
to our present state of knowledge the typical 
~‘mbryo-sac is a structure that stands isolated” 
pt, Monocotyledons. Unfortunately, | 
sone of the lowest of those forms is the development — 
Softee and a study of this process in the 
‘Of the above named groups is beyond qu 
