286 Phillips on a Comparative Study of the 
cause of this lack and its division by direct methods, he 
concluded that the central body was not likely a nucleus, 
though it might have had a common origin with that organ. 
Hegler, on the other hand, was able to find all stages of 
mitotic division in the central body and strongly affirmed 
its nuclear nature. Scott and Dangeard also recorded the 
mitotic division of the central body and its consequent 
nuclear character. Chodat and Malinesco did not consider 
the central body to be a nucleus, and later Chodat, publish- 
ing conjointly with Short, described the central body as a 
vacuolated portion of the cell contents, laden with slime 
balls. 
Thus the views concerning the central body of the Cyano- 
phycee differed. Some attributed to it a nuclear nature 
with mitotic divisions. Others considered it a nucleus, but 
with direct divisions. Still others regarded it as not a 
nucleus, but the phylogenetic progenitor of one, or that it 
originated from a common organ with the nucleus of higher 
plants though itself not representing that organ, while some 
looked upon the central body of these organisms as in no 
sense a nucleus or even functioning as such, even calling 
it a collection of vacuoles or, in one case, the cytoplasm. 
Whether the central body should be termed a cell nucleus 
depends entirely upon our definition of that organ. If our 
conception of nucleus is that it must have all the attributes 
of nuclear membrane, reticulum and nuclear sap, nucleolus, 
etc., as in the higher plants, together with a definite form, 
then this central body does not fulfill the requirements of the 
definition. But if we consider a nucleus to be a centre in 
which is located the hereditary material of the plant, and 
which governs the constructive activities of the cells, such 
as assimilation, growth and repair, also reproduction of 
form or structure, if in other words, we consider the nucleus 
from the physiologico-morphological side, then there can be 
no reason for denying the nuclear nature of the central body. 
Even measured by the first requirement above mentioned 
