2 adjectives to describe atomies

And yet those little particles, those mere atomies, might multiply and devastate a city!

Suppose that he extended his researches somewhat to those minuter vegetable forms, the mosses, fungi, lichens; suppose that he went a little further still, and tried what the microscope would show him in any stagnant pool, whether fresh water or salt, of Desmidiae, Diatoms, and all those wondrous atomies which seem as yet to defy our classification into plants or animals.

2 adjectives to describe  atomies