Odwalla’s Summertime Lime is sublime and Harvard Square’s Darwin’s Ltd. is Exclnt. The combination leaves something to be desired, though, as a small Summertime Lime at Darwin’s Ltd. will run you $3.29.

The experience of holding one for a moment and returning it to the refrigerator is free, though, which is what I did a couple of days ago. I was suddenly far less thirsty and far more curious about the actual cost of one of these little plastic bottles — especially since C’est Bon, only a couple of blocks away, was selling the roughly eight-ounce drink for only $2.99.

That’s still expensive. The Odwalla Web site’s frequently asked questions page includes a section on “Why are your juices more expensive than others?” and the wholesale cost of the beverages is information not shared with members of the public. So it’s not as though the company isn’t sensitive to the issue. But the same size Lime drink was $2.50 at Formaggio, on Huron Avenue, and, through today (with other Odwalla flavors), $2 at the Porter Square Star Market. Although $2.99 is a standard retail cost for the small bottle, it’s hard to believe Star isn’t making money on its Odwallas even by selling it at almost a dollar less.

Rent is higher in Harvard Square, of course, than in Porter, but it’s probably not 10 percent more on Mount Auburn Street, where Darwin’s Ltd. is, than on Massachusetts Avenue, where C’est Bon is.

Don’t get me wrong. Darwin’s Ltd. is a great place. It may be 10 percent better than C’est Bon. It’s probably 64.5 percent better than Star Market.

I’m not sure if it’s 31.6 percent better than Formaggio, though.