I WAS interested in Mr. T. Goodey's letter under the above heading in NATURE of March 13, but should like to make a few remarks thereon. Hay infusion, which Mr. Goodey states caused the ...

We have therefore subjected hay infusion to fractionation in order to isolate and identify the active excysting substance. Nature - Effects of Salts on Emergence from the Cyst in Protozoa.