Testing homogeneity of variances with Bartlett's test

Gives something like this:
Bartlett test of homogeneity of variances
data: con by trt
Bartlett's Ksquared = 12.1292, df = 2, pvalue = 0.002324
Bartlett test of homogeneity of variances
data: log(con) by trt
Bartlett's Ksquared = 0.8911, df = 2, pvalue = 0.6405

