We examined domains formed by two different lipids to investigate the influence of molecular structure on domain shape. In particular, we addressed the question as to whether domains of different lipids can exhibit a common form while maintaining their distinctive shapes. We chose dipalmitoylphosphatidylcholine and dimyristoylphosphatidylcholine because they share a common head group and differ only in the length of their hydrocarbon tails. Our results show that their domains do indeed exhibit a common form despite variations in detail imposed by the difference in chain length.