About the last of March my friend, Mr. Allen Curtiss, a botanist, brought me some Orange twigs infested with the Orange Scale Insect (Aspidiotus Gloverii). On examining them with my pocket lens, I was surprised to see numerons smail black mites running in and out of the scales, and which no doubt prey upon the eggs of the Scale Insect, and probably prevents their increase. Since then I have been enabled to examine them with a more powerful microscope,and I think they are entirely new to science.