Apparatus for specimen treatment

In apparatus for fixation, dessication, and embedding of biologic specimens for microscopic, especially electron microscopic studies, having a compartment for treating specimens held in liquid permeable specimen holders, a supply of treatment liquid, means connecting the supply to said compartment, and means to introduce liquid from the supply, and remove liquid from the compartment, the improvement comprising a chamber (14c) in said compartment for holding a quantity of fluid, a passage connected to said chamber, pump means (15) located in said chamber for moving fluid through said passage, at least one tubular cell (14a) for supporting a plurality of specimen holders (10, 10a) in an end to end relationship, one end of said cell being connected to said passage, the other end of each of said chamber and said cell being connected to a common portion of said tank to permit liquid to be circulated by said pump means.