A helicoidal surface in R3 is a
natural generalization of a surface of revolution. We give a simple description via
the theory of harmonic maps of the Gauss maps and Gaussian images of
complete helicoidal surfaces of constant mean curvature in R3. Do Carmo
had conjectured that the Gaussian image of such a surface contained an
equator. This is true for the complete surfaces of revolution of constant
mean curvatures in R3 and we affirm this for helicoids of constant mean
curvature.