458 



THE MICROSCOPE. 



The Acarus sacchari, Sugar insect. There is very com- 

 monly present in the more impure kinds of sugar, a beetle- 

 like animal of the genus Acarea. The discoveiy of the 

 very general presence of this acarus rests, we believe, 

 entirely with Dr. Hassall. 



The Sugar acarus approaches somewhat, in organisation 

 and habits, the Louse and the Itch-insect; it is in size so 

 considerable, that it is plainly visible to the unaided sight. 



Fi. 222. 



Ova and young of the Acarus sacchari, Sugar-Insect, after Hassall, magnified 

 200 diameters. 



When present in sugar, it may always be defected by the 

 following proceeding : two or three drachms or teaspoorisful 

 of sugar should be dissolved in a large wine-glass of tepid 

 water, and the solution allowed to remain at rest for an 

 hour or so; at the end of that time the animals will be found, 

 some on the surface of the liquid, some adhering to the sides 

 of the glass, and others at the bottom, mixed up with the 

 copious and dark sediment, formed of fragments of cane, 

 woody fibre, grit, dirt, and starch-granules, which usually 

 subside on the solution of even a small quantity of sugar in 

 water. The acarus in question will be found to agree with 

 the following brief description, premising, in the first place, 

 that its development may be clearly traced out in almost 

 every sample of brown sugar. The Acarus sacchari is first 

 visible as a rounded body, or egg; this gradually enlarges, 

 and becomes elongated and cylindrical, until it is about 



