108 SIDNEY F. HARMER. 
Fig. 20 is from a colony which possessed three polypides only, 
each of them being accompanied by a brown body. The fertile 
zocecium is almost certainly z?, but if not itis z’. The structures 
connected with the embryo show a distinct advance in develop- 
ment. The follicle is more fully formed, and there is also pre- 
sent an elongated group of nuclei which is easily recognised as 
the “suspensor” of the next stage. 
My notes show a perfectly consistent result with regard to 
the age of the colony at which this stage is passed through. 
This is brought out by the following table: 
Embryos in Stage B. 
No. of colonies 
Colonies possessing three polypides only 7 5 “ 16 
+f r four or five polypides_ . : : 3 
Colony larger, the fertile zocecium being younger than z? or 23 1 
Sections not good and result uncertain : ; : 5 
Total number of colonies examined . : : 25 
It is clear that Stage B is most commonly passed through in 
colonies which contain three fully developed polypides, with 
perhaps one or two young buds in younger zoecia. The mea- 
surements of the colonies are remarkably uniform at this 
stage, the total length of the colony (in section) ranging from 
‘40 to ‘48 mm. 
It may be noted that although most of the above colonies 
were in the three-polypide stage, it does not follow that any 
colony containing that number of polypides will also contain 
an embryo in Stage B. We have already seen that a consider- 
able number of these colonies contain eggs. In some cases, 
moreover, it appears that the polypides may be well formed in 
z'—z3 before any of these zocecia undergo a histolysis of their 
polypide, or at least before the polypides of z? and 2° experi- 
ence that fate. Now since the occurrence of a brown body is 
all but universal in all fertile zocecia, of whatever age, and 
probably occurs in all fertile zocecia which are developing 
normally, we can hardly expect to find an embryo in any z? or 
z in which the first polypide of the zocecium has not had time 
