Thanks everyone - that has made things a bit easier! One I am sure is female, but the other has slightly longer horn nubs, but not as big as Monty's. They are small, thin 'points' rather than proper conical horns like Monty has. Neither us nor the breeder has ever raised baby Jacksons before so we don't know how long the females show nubs for. All the babies in the clutch had nubs at two weeks when I first saw them. I may ask if I can post his pics or if he will join the forum. So I guess my next question is - when do the female Xanths lose their nubs? Is it possible that they may always have them or do they always disappear?