The specificity of a complement-fixation test for schistosomiasis, using as antigen a buffered saline extract of ether-extracted adult worms, was evaluated in other helminthic infections. No serologic reactions were observed with the sera of 39 nematode-infected natives of Trinidad, an island whose natives have never been found to have schistosomiasis. The sera of only two of 69 nematode-infected Puerto Ricans without overt evidence of schistosomiasis were reactive. Two of 8 Japanese infected with P. westermani reacted in the test for schistosomiasis.
Present address, Fifth U. S. Army Medical Laboratory, 12th & Spruce Streets, St. Louis 2, Missouri.