The Crystal Structures of 2-Phenyl-3,3-dimethyl-1,1-dichlorocyclopropane (I), 2-p-Chlorophenyl-3,3-dimethyl-1,1-dichlorocyclopropane (II) and 2-p-Chlorophenyl-3,3-dimethyl-1,1-dimethoxycyclopropane (III).