80 SIDNEY F. HARMER. 
grows at the commencement of the formation of the colony. 
The whole colony acquires a certain symmetry with regard to 
3, the axial zocecium, and in studying the characteristics of 2 
and 3 it matters not which of these corresponds with B and 
which with cin I of the diagram. The necessity for a close 
attention to these zocecia will become apparent later. 
The distinction between right- and left-handed colonies per- 
sists throughout life, although it ceases to be obvious in colo- 
nies of more thana certain age, when looked at in the usual 
position, from above. The difference can readily be appreciated 
in young colonies, in which the early stages of the embryonic 
development are taking place. This will be seen by comparing 
fig. 3 (left-handed) with fig. 4 (right-handed). 
The two kinds of colonies seem to occur in about equal 
numbers. Of sixteen chosen at random as a test case, eight 
were right-handed and eight were left-handed ; and this result 
agrees with the other observations I have made on this point. 
The actual position of the three zoccia can be seen from 
fig. 2, which is an end view of a young colony which was 
proved to be left-handed by examining it in another position. 
1 is the primary zoccium, which in future will be designated 
by the symbol z!, the symbols z? and z> being employed for 
the zocecia 2 and 3 respectively in either 1V or V of the wood- 
cut (p. 78). The tubular end of 2? has in fig. 2 reached a 
higher stage of development than that of z). zis in contact 
with the surface of attachment, while z! and z? are on the 
free surface of the colony. The position of these three zoccia 
is also shown in fig. 3, a somewhat later stage seen from above. 
The colony may be described as having the form of a flattened 
funnel, whose narrow end originates in the disc. The funnel 
is attached by one of its flattened sides ; and its lip, which is 
closely attached to the seaweed on this side, here projects 
considerably further than on the opposite side. The wide end 
of the funnel is, in fact, obliquely truncated. 
2° has acquired an axial position, which it retains through- 
out the later development. z! and z’ are, at their upper ends, 
arranged symmetrically with regard to z°, although the wood- 
