2 
Harper and Dodge. — The Formation of the 
endeavoured to find an analogy between the function of the centrosome 
here and its function as a blepharoplast in the formation of the cilia of 
motile male cells, &c., or as the centre of a system of astral rays in the 
formation of the bounding membrane of the ascospore. According to 
Kranzlin certain nuclei start to divide but form only a unipolar (heteropolar) 
spindle. The centrosome of this heteropolar spindle becomes an ‘ elatero- 
plast’ and marks the starting-point of a capillitial vacuole, and becomes 
thus the initial organ in the formation of a capillitial thread. The rays 
tend to disappear with the full development of the vacuole, and are pro- 
bably to be considered only as the ‘visible expression of the chemical 
relations between the expanding vacuole and the cytoplasm which surrounds 
it \ Miss Kranzlin’s conception is that the capillitial threads are to be 
phylogenetically derived from flagella. 
Our studies have been extended to a number of forms, with the result 
that everywhere these radial fibrillar systems have been found at a definite 
stage in the development of the capillitium. 
The figures in Hemiarcyria clavata and Trichia fix readily and stain 
sharply, and may be taken as typical for forms having a thread-like hollow 
capillitium with more or less spiral or annular thickenings. Our material 
was fixed in Flemming’s weaker solution and stained with the familiar 
triple combination, safranin, gentian violet, and orange G, and with iron- 
haematoxylin. 
The creeping out and development of the sporanges of Hemiarcyria is 
only a matter of a night or even a few hours under favourable conditions. 
Our material was largely obtained from specimens grown on rotten logs 
kept moist in a Wardian case in the greenhouse, so that material of known 
age could be fixed at all stages of development. It is not altogether easy 
to get complete series of stages from single collections of material in 
the field. 
It is also of the greatest importance that the material be fixed at 
once without unnecessary jarring or disturbance. Jarring causes the most 
palpable disorganization of the protoplasm, and the resulting figures, while 
not easy to characterize in a word, leave no question as to their abnormality. 
This is especially true in the case of the developing sporanges of 
Stemonitis. 
The formation of the capillitium begins practically as soon as the 
sporange has reached its full size. It precedes spore formation, and there 
is no evidence of the initiation of progressive cleavage before the capillitium 
is completely formed. 
Prior to the formation of the capillitium the cytoplasm is rather 
homogeneous, the nuclei are evenly distributed, and there are no large 
vacuoles, though the sponge-like network of the cytoplasm may be more 
open towards the centre of the sporange. In Trichia and Lycogala at this 
