Color excesses for 24 galactic cepheids were determined by Kron and Svolopoulos. 1 Their calculations were based on a thermal locus and reddening line derived from six-color observations of 139 supergiant stars. 2 This note extends the study to four galactic cepheids in the Southern Hemisphere, including ß Doradus which is in the field of the Large Magellanic Cloud. Twenty-eight six-color observations of the four southern cepheids where made during 19 nights from October 1960 to April 1961.

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... were obtained at the two-mirror Cassegrain focus of the 26-inch Mount Bingar and the 50-inch Mount Stromlo reflectors, and at the three-mirror Cassegrain focus of the 29-inch Reynolds Mount Stromlo reflector. A refrigerated RCA 7102 photomultiplier was used for all the observations. All data were reduced to the six-color system of Stebbins and Whitford. 3 Table I contains the observational data. The epoch and period for each cepheid were taken from the General Catalogue of Variable Stars* The last three columns give the differences V -B and R -I and the derived color excess, E P _ v , calculated using the thermal locus and reddening line given by Kron. 2 Additional six-color observations, made in 1960-61, of supergiant stars increase the weight of this locus. 5 The writers would like to thank Professor Bart J. Bok for permission to use the facilities of the Mount Stromlo Observatory.