552 Transactions. 
having a diameter of 2-5 cm. for the holdfast and 3 mm. for the stipe. In 
some large specimens the holdfast measures from 30 cm. to 60 cm. across, 
and in these it is not uncommon to see several stipes arising from one 
holdfast: Agardh (1848, p. 188) mentions six as the highest number 
observed; the writer has seen four, three adult plants, several feet in 
Ето. 1.—Holdfast, with portion of sti i i 
А pe showing pits, &c. 
Fie. 2.—Small plant of Durvillea antarctica ( х 4). 
Where the plants grow together in such masses that the holdfasts of the 
separate plants have not sufficient room to develop independently, one will 
encroach on another, the two finally growing together, forming one common 
holdfast in which the tissues have united so completely that there is in 
most cases no mark to show where the union has taken place. А 
= c Specimen examined the stipe seemed to branch just at its 
Junction with the holdfast; but this apparent branching was probably 
brought about by the germination of two oospheres close together, 80 that 
the two holdfasts united at a very early stage, while the two stipes by gro 
