Summary

Di hydranol diluted 1:1000 with Locke-Lewis solution kills tissue cultures at once in situ.

Emetine hydrochloride 1:1000 acts more slowly on the cells, killing them in twenty-four hours.

Yatren 1:1000 kills most of the cells in twenty-four hours. The process is a gradual one.

The de Rivas solution 1:1000 is not very toxic for the tissue cultures. The tissues are normal with the exception of a few outer fibroblasts which contracted.

When di hydranol 1:1000 was added to tissue cultures for one hour and for one-half hour and was then replaced with Locke-Lewis solution there was no recovery.

When emetine hydrochloride 1:1000 was added to tissue cultures for one hour and for one-half hour and was then replaced with Locke-Lewis solution the cells gradually died and disintegrated.

When yatren 1:1000 was added to the tissue cultures for one hour and for one-half hour and was then replaced with Locke-Lewis solution there was some recovery.

When de Rivas solution 1:1000 was added to tissue cultures for one hour and for one-half hour and was then replaced with Locke-Lewis solution the tissue remained normal and growth was excellent.

Di hydranol 1:10,000 kills the cells farthest away from the explant. These are replaced by cells migrating out from the expant

Emetine hydrochloride 1:10,000 kills the cells after forty-eight hours treatment.

Yatren 1:10,000 slightly retards growth.

de Rivas solution 1:10,000 does not affect the tissue cultures.

Di hydranol 1:50,000 injures some of the outer fibroblasts. The cells soon adjust themselves to the solutions and growth continues normally.

Emetine hydrochloride 1:50,000 acts slowly but after forty-eight hours most of the tissue culture cells are dead and have disintegrated.

Yatren 1:50,000 injures only a few of the outer fibroblasts. The tissue cultures grow well in this medium.

de Rivas solution 1:50,000 does not injure the tissue culture cells.

Emetine hydrochloride 1:100,000 kills the tissue culture cells or injures them so that they are abnormal.