Dear Nhu Nguyen, I was totally surprised by your most recent posting. It seemed to be in flat contradiction with the key in 'What is a Bulb', inserted to define what was acceptable to PBS as a bulb. I thought that was meant to provide the defining word here. Question 2 of the key says: "2. Is the plant generally recognized to grow from some sort of thickened storage organ (a bulb, tuber, corm, thickened rhizome, thickened root, or fleshy pseudobulb)? In other words, would scientists call it a geophyte? If the answer is yes, we include it. If no, go to question 3". Thus, the presence of a thickened storage organ is a criterion for acceptance, which means that orchids possessing fleshy pseudobulbs are accepted. If you have subsquently decided not to include them you had better correct the key. I wrote a message here yesterday showing an orchid with a massive set of fleshy pseudobulbs. It would certainly be far closer to what we think of as a clump of bulbs than so many other genera considered here. Indeed the pseudo bulbs do look comparable to your example of 'Crinum and Ismene'. Living atop granite outcrops the orchid cited uses its massive pseudobulb system to store water during the long, cool dry season. If the preference of PBS to eliminate such plants, so be it, but you then really do need to reformulate 'what is a bulb'. Andrew San Diego