| 
} 
1899] CURRENT LITERATURE 149 
A RECENT PAPER by Dr. B. M. Davis? is of more than usual interest, as 
it contains the first description of the process of nuclear division in one of the 
Rhodophyceze. The studies were carried on at Naples and at Bonn, and the 
tetraspore mother-cell of Corallina, one of the lime-encrusted red algae, was 
selected. The nuclear figure in metakinesis is especially interesting because 
of the remarkable differentiation of the kinoplasm into two beautiful centro- 
sphere-like bodies at the poles of the spindle. The centrospheres are very 
large homogeneous bodies without centrosomes. They arise from accumula- 
tions of kinoplasm at the opposite ends of elongated nuclei entering prophase 
conditions. The spindle fibers develop from these regions of differentiated 
protoplasm, finally appearing as extensions from the outer surface of the cen- 
heres. The chromatin is scattered in a very finely divided condition 
the nuclear plasm, which is homogeneous in structure and lacks the 
usual linin network. After the division at the nuclear ‘plate the two sets of 
split chromosomes are drawn up to the centrospheres, finally lying against 
, at first smaller than the chromatin body but soon growing 
The chromatin body begins to fragment, which process finally 
hat material to the form of minute granules inside the nucleus and 
The centrosphere completely disappears 
gion of the protoplasm, leaving no trace of its former 
It seems to be the morphological expression of certain activities 
Ee” concerned with nuclear division. Thee ie wo evidence 
permanent organ of the cell.— Mee 
of the prot 
that it is a 
* Kernthei : . 
raneq, a in der Tetraspormutterzelle bei Corallina officinale L. var. mediter- 
9 
- deut. botan. Gesell. 16 : 266 
