Vol. 34 
BULLETIN ie 
TORREY BOTANICAL CLUB 
; JUNE, 1907 
The embryology of Rhizophora Mangle 
MELVILLE THURSTON Cook 
(WITH PLATES 22 AND 23) 
q The peculiar habit of the mangrove (Akizophora Mangle Ia); 
of germinating the seed while yet on the tree, has attracted con- 
‘Siderable attention, and it has been the subject for observation and 
Mvestigation by a number of persons, The most important 
investigations on the embryology were made by Karsten * on this 
and telated species and genera, and on species which have similar 
habit but are classed in entirely different families ; but the results 
of his work on this particular species were very meager, 
_ The study of this Species presents many difficulties, and it was 
y after repeated efforts that the author succeeded in getting the 
‘parations on which this paper is based. A few stages are 
ing, but since it is impossible for the author to secure more 
aterial at this time it was thought best to publish the results of 
investigations, 
In general it may be said that the picric acid killing and fixing 
ents were most successful, but the preparation which gave the 
St results was a mixture of 98 c.c, saturated aqueous solution of 
“IC acid with 2 c.c. sulphuric acid. 
Only one of the four ovules is fertilized (FIGURE 1), and this 
S while the other three atrophy (FIGURE 13). The ovaries 
4 ovules did not always increase in size with the same rapidity, 
that it was not always possible to judge the age and condition 
the internal structures by the size of the ovary or ovule, as will 
ie se 
* Karsten, G, Ueber die Mangrove-Vegetation im Malayischen Archipel. Eine 
ologisch-biologische Studie. Bibliotheca Botanica, Heft 22 (5: 1-71). 1891. 
© BULLETIN for May 1907 (34: 221-270, p/. +7-27) was issued 10 Jl 1 907. ] 
271 
