Newcombe. — Cellulose-Enzymes . 
79 
those of Barley-malt and Aspergillus , were still able to 
dissolve the endosperm-walls of the Barley when the ferment- 
solutions were so much diluted as to require ten times as 
long as required by strong solutions to convert the starch 
in a starch-paste. 
Of the five strongly cytohydrolytic enzymes used in this 
work, all dissolve starch. But the extract of the Lupin 
and the two extracts from the Date-seedlings act so 
feebly on starch that they certainly cannot be denominated 
diastase. When the strongest solutions that could be made 
of the three ferments last mentioned required from twenty- 
four to fifty times as long as a strong Barley-malt-extract to 
dissolve starch-grains or hydrolyze the starch in starch-paste, 
and when such enzymes, so slightly acting upon starch, act 
very intensely on cell-membranes, obviously the enzymes of 
the Lupin and the Date are cytohydrolysts and not diastase. 
The question proposes itself as to whether we have in each 
of the five enzyme-extracts under consideration a mixture of 
an amylohydrolytic and a cytohydrolytic ferment, or in each 
extract a single ferment with peculiar properties. So far as 
I can perceive there is no certain evidence for the one 
assumption or for the other. It would, however, to my mind, 
seem remarkable that two single ferments behaving so much 
alike toward reserve cellulose as do those of the Barley and 
the Lupin should attack starch with such unlike intensity, 
and yet should both attack it. With this hypothesis we 
should be compelled to assume that the extracts of the 
Barley and the Aspergilhis are not diastase in the accepted 
meaning of the term, but ferments with the properties of both 
diastase and cytase possessed nearly equally ; and we should 
be compelled to assume that the extracts of the Lupin and 
the Date are cytase which has the power of slightly dis- 
solving starch. 
On the other hand, there are various features favouring 
the view that these extracts with the properties of diastase 
and cytase are not simple, but are mixtures. In the first 
place, though a plant-diastase neutral toward reserve cellulose 
