88 UTILIZATION OF MINUTE LIFE. 



liquid sugar; and this, as we have seen, is the 

 composition of honey. This discovery is owed to 

 Braconnot. 



Mannite, the sweet principle of manna, has been 

 found, though rarely, in some kinds of honey. 



The manna that is used as an agreeable food in 

 the East, and with us as a purgative for children, 

 is caused to flow from the Tamarix mannifera (Fig. 

 7), by the punctures of a small insect, Coccus mani- 

 parus. But it is essentially a vegetable product, 



FIG. 7. Tamarix mannifera (Manna-bearing Tamarix). 

 1. Shrub twelve feet high. 2. Branch with fruit. 



being obtained from the sap of the ash tree (Frax- 

 inus ornus, F. rotundifolia, etc.). The little green 

 aphides of the lime tree appear, however, to secrete 

 mannite from their bodies, on account of which 

 they are captured and reared by ants as we breed 

 cows for their milk. But it has not yet been 

 proved that any animals produce mannite directly, 

 though sugar is a common product of the animal 



