I think I've just acquired this plant, or one extremely similar to it. Mine has those 'spines' ony around on section of the body, and at the very top, nowhere else. Is this usual for this plant ? Does it start out with a spine on each, not sure of the correct term here, tubercle or areole ?, and then shed them later or perhaps they are just very vulnerable to injury ? Got any idea how large this can get or whether it will branch on it's own ? Great pix in this album, btw - been a pleasure rummaging thru it. Thx. Karen