it's fucked that these things are inedible and toxic. they should taste like key lime

56k warning
it's fucked that these things are inedible and toxic. they should taste like key lime
What are they? Also, what is going on with those leaves that look like they're... dissolving from inside their edges?!
if I'm remembering my 1970s British kids' fictional alien field guide correctly, these are the gas-filled orbs that are depicted exploding and shattering the faceplate of an astronaut who has unwisely disturbed their tendrils, while some towering columnar creature strides through the background exhaling uranium hexafluoride vapour