|MadSci Network: Zoology|
Sorry I took so long to answer, been swamped with the snake research. The 'chameleon' you are referring to is the anole (Anolis carolinis) commonly found in the SE US (and just about every pet store) and is also called the American chameleon. The red sack is used in mating rituals to attract females. Cheers, Bryan Australian Venom & Toxin Database http://www.uq.edu.au/~ddbfry/index.html
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