244 On a New Sjjecies of Manna 



When treated with potash under the microscope, they 

 became very transparent, and lost their graniihir appear- 

 ance, and a drop of sokition of iodine coloured them 

 uniformly blue ; thus indicating starch as one of their 

 constituents. The cup itself is composed entirely of a 

 mass of cells resembling stai'ch-globules, but so closely 

 compacted together, that their characters can only with 

 difficulty be made out. A thin slice, however, when 

 macerated for some time in water, admitted of disinte- 

 gration ; and though most of the cells were broken up, a 

 few could be distinguished in a pretty perfect state, and 

 agreed m their appearance with those of starch. The 

 whole cup is coloured blue by iodine. 



The taste of lerp is distinctly saccharine, but this is 

 confined entirely to the hairs ; the cup when completely 

 separated presenting only a slight mucilaginous taste. 



The chemical examination showed that it differed as 

 remarkably in constitution, as it does in form, from all 

 hitherto examined species of manna. When boiled Avith 

 alcohol, a large proportion is dissolved ; but the solution 

 deposits no mannite on standing, and when evaporated 

 on the water-bath yields a thick syrup, which cannot be 

 brought to crystalhse. It is obvious from this fact, that 

 it contains neither mannite nor the sugar obtained by 

 Johnston from the manna of Eucalyptus mannij'era. The 

 sugar separated from lerp had all the characters of the 

 uncrystallisable sugar obtained from fruits, and entered 

 rapidly into fermentation when mixed with yeast. The 

 residue from wdiich the sugar had been extracted yielded to 

 cold Avater a small portion of gummy matter, and, when 

 boiled with water, a considerable part of it dissolved ; 

 and the filtered solution, on cooling, deposited a large 

 quantity of a white powder, of sparing solubility in cold 

 water. The fluid from which this substance had separated 

 gave, with iodine, a strong reaction of starch. 



The substance which deposited from the hot solution when 

 washed wath hot Avater until it no longer gave the reaction 

 of starch was found to agree, in all its characters, with 

 inulin ; but in order fully to establish its identity, an 

 analysis w^as made of the substance dried at 310°, of 

 Avhicli the following are the details : — • 

 [ 6 "441 grains gave 

 \ 10'398 .... of carbonic acid, and 

 I 3 652 .... of water. 



