What Snape knew

[meglet2]

No: HPFGUIDX 35287

I've been re-reading for the umpteenth time POA (my favourite). In 
the Shrieking Shack as Remus is launching into the story he breaks 
off because there is a 'loud creak behind him' and the bedroom door 
opens of its own accord. The point at which Snape enters in Harry's 
invisibility cloak. That means he hears all the story of the three 
illegal animagi and from that point knows Sirius is an animagus. He 
also hears Remus descibe the making of the Marauders Map and list 
their nicknames though he must have known some of that before when 
he thought Harry had got it direct from the manufacturers. At any 
rate he has certainly now heard Peter described as Wormtial and some 
posts a while ago were speculating that he had heard about a fellow 
DE called Wormtail while he was in or pretending to be in 
Voldemort's service and assumed that was Sirius. Was he simply too 
angry to take in this information in the SS because in GOF he seems 
to have forgotten that Sirius was an animagus and he reacts in the 
SS as though he has no idea other than that Sirius is guilty as 
hell? Or is there any other explanation of his subsequent behaviour 
to Sirius and the bitterness of his attack on Lupin?

meglet2/Mercia