1898-99. | ON THE CYTOLOGY OF NON-NUCLEATED ORGANISMS. 461 
body is at least an indication of the occurrence therein of an iron-holding 
nuclein, like, in some respects at least, the chromatin of the nuclei of 
higher organisms. This conclusion is supported by the results of the 
action of artificial digestive reagents in these organisms, 
When fresh trichomes of Osczllaria, Tolypothrix, Scytonema and Micro- 
coleus were digested with artificial gastric juice, made by adding a 
quantity of a strong glycerine extract of the mucosa of the gastric 
fundus of the pig to hydrochloric acid of 0.2 per cent. strength, the 
preparations at the end of forty-eight, seventy-two and ninety-six hours 
showed certain changes which were due to the digestive reaction. 
Zacharias found that the peripheral zone is in great part removed, while 
a portion of the central body disappears leaving two substances behind, 
one of the nature of plastin, the other having a nuclein-like character 
and receiving from him the name, “central substance.” Fischer, on the 
other hand, denies that the digestive reagent has any such effect and that 
the diminution of the volume of the contents is due to a contracting 
action of the digestive ferment in the presence of hydrochloric acid, an 
action which he terms enzymatic. _ Fischer’s view is incorrect for when 
one studies at some length the digestive action of artificial gastric juice 
on the cells in Cyanophycez, not only is there a diminution in the 
volume of the cell contents but there is also a disappearance of a portion 
of its constituents. The peripheral zone is perhaps most affected but a 
portion of it resists digestion, and after treatment with weak potash 
solution (0.3 per cent.) remains. This latter substance is undoubtedly 
plastin. The central body also is affected, but at first sight apparently 
less so than the peripheral zone. It is rarely diminished in size and it 
has, as Zacharias points out, specially after treatment with alcohol and 
ether, a nuclein-like lustre. When, however, the preparation, after pro- 
longed treatment with alcohol and ether, is stained in a good alum- 
hzmatoxylin solution (Ehrlich’s or Delafield’s) the central body, instead 
of appearing homogeneous or appearing uniformly stained as in good 
fixed preparations, gives in the majority of cases a coarse reticular 
appearance in which the trabecule are usually deeply stained. (Fig. 8). 
The stainable portion of the central body, the “central substance” of 
Zacharias, is soluble in weak alkalies, as may be proved by placing 
trichomes, acted on by gastric juice for forty-eight hours, in a 0.3 per 
cent. solution of potash for six or seven hours, when subsequent treat- 
ment with ether, alcohol, and Ehrlich’s hematoxylin fails to indicate the 
occurrence of a stainable substance like that referred to. What remains 
of the central body and of the peripheral zone stains, but there is no 
differentiation, both parts staining feebly but uniformly. This indicates 
