344 DR. SARAH М. BAKER AND MISS М. Н. BOHLING ON 
developed and divided in the usual way, and in every case examined the 
proportion of the sexes in any one conceptacle was approximately equal. 
But in both the marsh forms described above, the reproductive organs were 
abnormal. Onthe dwarf embedded form they were very rare, but they were 
freely produced upon the attached form. In all cases, however, the oogonia, 
although occasionally reaching full size, were undivided, and there was, in 
addition to this, а great variability in the proportions of the two sexes in any 
one receptacle. Оп the same plant, and often in the same receptacle, all 
stages could be found, from a normal, equally divided, hermaphrodite 
conceptacle to one containing a great preponderance of antheridia, and. 
Fre. 11.— Fucus ceranoides megecad limicola. Nat. size. 
Embedded with Heleocharis, lower zone; plant showing receptacles. Keyhaven, Hants. 
finally, to a pure male conceptacle. In the same way the transitions were 
shown, through a preponderatingly female conceptacle to a pure female опе. 
This extraordinary variability is very interesting in view of the well-known 
property of F. ceranoides of forming either hermaphrodite or dioecious plants. 
It seems as though the new conditions incidental to the marsh habit had, 
in some way, upset the equilibrium of the reproductive mechanism of the 
plant; so that the hermaphrodite and the dioecious factors, whatever they 
may be, became mingled in irregular proportions throughout the organism. 
The reasons for these peculiarities in the marsh form of F. ceranoides will be 
diseussed later. 
