Salt glands are fascinating anatomically and physiologically. If you've never read the great SCHMIDT-NIELSEN's work, here's a link to an OA paper on "The salt-secreting glands of marine birds", from 1960. (http://circ.ahajournals.org/content/21/5/955.abstract).
Salt glands seem to be an example of convergent evolution. They've arisen repeatedly to deal with the problem salt elimination without too much water loss. They are a terrific tool to help students learn about the movement of ions across membranes.
Here are a few review articles with more information about salt glands and other halophyte adaptations:
Flowers and Colmer, New Phytol 2008 (http://onlinelibrary.wiley.com/doi/10.1111/j.1469-8137.2008.02531.x/full)
Munns and Tester, Annu Rev Plant Biol 2008 (http://www.annualreviews.org/doi/abs/10.1146/annurev.arplant.59.032607.092911?journalCode=arplant)
Flowers et al, Functional Plant Biol. 2010 (http://www.tempoandmode.com/wp-content/uploads/2010/07/flowersevolutionhalophytesfuncplbiol10.pdf)and from
Via Mary Williams