CONTROL of the snail intermediate host involved in transmission of schistosomiasis is being attempted in many countries. In the Western Hemisphere copper sulfate and sodium pentachlorophenate (NaPCP) ha,ve been used in attempts to control Awutralorb1,s glabratus (1, 2), but to date schistosomiasis continues to persist in many parts of tropical America,. In recent years the pesticide industry has developed numerous chemicals, certain of which possess molluscicidal properties. The studies reported here consisted of laboratory evaluation of 28 candidate compounds and field appraisal of the effectiveness of promising candidates against A. glabratus. The compounds tested are listed below by trade name and chemical name; the letters in parentheses are supply references. acrolein (A): acrylaldehyde Bayer 73 (B): 2-Aminoethanol salt of 2',5-dichloro-4'nitrosalicylanilide carbaryl (C) : 1-naphthyl N-methylearb,amate copper sulfate: copper sulfate dichlorvos (D) : 0-2,2-dichlorovinyl 0,0-dimethyl phosphate disodium endothal (E) : disodium salt of 3,6-endohexahydrophthalic acid DN-1 (F): dinitro-O-cyclohexylphenol Dybar (G) : phenyldimethylurea Eelicide-TFM (H): sodium salt of 3-trifluoromethyl-4nitrophenol FD-75 (I) : alkenyl dimethyl ethyl ammonium bromide GC-1283 (J) : do,decachlorooctahydro-1,3,4-metheno-2Hcyclobuta (cd) penitalene HRS-230 (K) : hexachloro-2-cyclopentenone HRS-1243 (K) : decachloropentacyclodecanone glycerol adduct HRS-1362 (K): decachloropentacyclodecanone acetamide adduct HRS-1603 (K): 2,3,6-trichlorobenzyl-oxypropanol and 2,4-D ICI-24223 (L) : isobutyltriphenyl methylamine Kepone (J): decachlorooctahydro-1,3,4-metheno-2Hcyclobuta (cd) pentalen-2-one Kuron (F): 2(2,4,5-trichlorophenoxy) proplionic acid NaPCP: sodium pentachlorophenate Pentac (K): bis (pentachlorocyclopentadienyl) TD-47 (E): di N,N dimethylcocoamine salt of 3,6 endoxohexahydrophthalic acid TD-191 (E) : mono, N,N dimethylcoco,amine salt of 3,6 endoxohexahydrophthalic acid Tritac (K) : 2,3,6Otrichlorobenzyloxypropanol Win 4257-2 (M): monosodium salt of 2,2-dihydroxy3,3',5,5' tetrachloro diphenyl sulfide Win-4257-17 (M) : disodium salt of Win 4257-2 Zectran (F) : methyl-4-dimethylamino-3,5-xylyl carbamate Ziram (G): zinc dimethyldithiocarbamate Zytron (F) : 0(2,4-dichlorophenyl) 0-methyl isopropylphosphoramidothioate