http://lepcurious.blogspot.co.uk/) Kirsten informs me that these are in fact the chrysalises of Queens, Danaus gilippus. These were about 20mm long. I love the row of golden dots around the top, just like a golden zipper! I had been concerned that out of 20, or so, chrysalises only two were green, with the others being a buff colour, but Kirsten assures me that this is normal for Queen chrysalises.
I was also slightly concerned that the chrysalises were within easy reach and it would be easy for kids to poke them or any newly eclosed butterflies. I suppose this can't be a problem, or they would have changed how they display the chrysalises. Actually, the last time we visited Butterfly World the chrysalises were all behind glass, so it is a big improvement to be able to get a close look at them.
I find the whole process of caterpillars turning into chrysalises, then turning into butterflies really fascinating. For me, the range of chrysalises at Butterfly World was just as interesting as the butterflies themselves.