The development and production of a disintegrating tablet as a practical means of employing phenothiazine as an anthelmintic for sheep are further described. Continued critical tests have shown high efficiencies against Oesophagostomum, Haemonchus, Ostertagia, Monodontus, Nematodirus, Cooperia, Trichostrongylus, and Chabertia. Tests against single infections with Ostertagia continued to show the complete efficiency of this form of treatment against this parasite. The periods of excretion of destroyed parasites with the faeces are noted. Single doses of phenothiazine did not anaematize animals under treatment.