Hey all, I have some Cacti that I've added to my collection over the past year that I'm having major difficulty identifying they all have some quite strange features. I have a few cacti books but can't seem to find them anywhere. I wondered if anyone could help.

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This one I'm not sure but I suspected it was some kind of Rebutia. The white fur on the top of the cactus threw me off though, I can't find any references to cacti like this with fur and flowers, it kind of looks like a green christmas pudding :P

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This cactus is similar perhaps a Mammilaria, it has dense, short spines and some wispy fur, but it is the red nodules that confuse me. I think they are flowers but they don't open, they just grow, then shrivel up. The form a ring around the cactus at a constant 'latitude'

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This is the strangest I think. It is a branching cactus, you can see a little branch to the bottom right. The spines start of as green and soft with spinelets on the spines, looking like little shoots, and then they either go bright red and eventually brown and hard, or they become branches. I've heard of many cacti where branches and spines are borne from the same areole, but never seen one before where they start growing before they have decided whether to be a spine or a branch. They look like the spiny back of some kind of green demon.