302 R. T. BAKEK AND H. G. SMITH. 
The ninth twenty-four hours gave 0:3 + 
», tenth ” ” 2°8 ” 
» eleventh we ww 00 
» twelfth ; — 20 Pe 
It will be observed that during the last few days the rate of 
decomposition was very irregular. The temperature during each 
day was from 80° to 85° F.. when highest. No further gas was 
obtained after the twelfth day, so that the product was 32 ce. of 
gas. After the first few days there had been obtained more than 
sufficient gas to account for the whole of the sugar found to be 
present in the manna. It is evident, therefore, that the decom- 
position of other substances must have taken place. It is generally 
accepted that mannite itself does not ferment with ordinary yeast. 
It is thus difficult to understand what other substances can be 
present in the manna to be decomposed by yeast, with the form- 
ation of CO,, if the mannite is not acted upon. The reaction 
may be probably due to the presence of the organisms found in 
the manna, acting with the yeast introduced. The organisms in 
the manna have the power of decomposing cane sugar, under 
certain conditions, with the evolution of gas. The subject is 
extremely interesting and worthy of more research, and as we are 
expecting to receive shortly much more material, the matter will 
be further investigated. The CO, calculated theoretically from 
the volume obtained, is equivalent to 14:33 per cent. of sugar 
considered as glucose, which is more than four times as much as 
was found to be present in the manna, 
This is the second record of the occurrence of a true manna in 
Australia. The first being described by J. H. Maiden, ¥.1.s.,' 2 
an exudation from Myoporum platycarpum, R.Br. 
Our specimen is quite distinct from either the Eucalyptus 
manna, or lerp,as these substances contain sugars and not mannite. 
This latter is found in the dried juice which exudes from the 
Manna Ash (Fraxinus ornus). Mannite occurs in many other 
1 Op. cit. 
