Hi VirginiaBelle, what gorgeous glasses! Looking at them the stems would appear to be seahorses rather than dolphins though? Your pictures are displaying just fine for me, so I suspect the problem is being caused by your browser settings needing a tweak somewhere.
I can't help you re confirming the maker as Salviati - that's what I would assume they are on seeing the pics - but I'm sure someone with more knowledge will come along and help you out.