They are the stinky-mouth chameleons? When threatened they sling stinky goo from sacks on the corners of their mouths all over the place. Don't think these guys will make good pets.
From the article
"Threatened individuals of T. conirostratus (both sexes and juveniles) would open their mouths, yet, rarely would they bite when handled. Rather, it seemed that opening the mouth served a dual purpose: intimidate and expose temporal pouches (i.e., corner of jaw) (Fig. 4). These pouches were often filled with a yellow/orange or brown material that had an astringent odor and was similar in consistency to partially digested food (Fig. 4A). When handled, chameleons would open their mouths, expose the pouches, and extrude this substance. Simultaneously, chameleons would thrash their heads from side to side; an action that often distributed the substance onto the collector’s hand (Fig. 4B). The foul-smelling scent from the smeared material remained on the collector for ca. 24 hours post-washing with soap."