2. The yellow seed inside is the 'real' seed. If you put it on your desk, 'feel' it with your fingertip. If you feel something 'thick', the seed is potential viable
3. The clear disc is not a problem, the seeds will germinate if they are viable. Only if you sow in vermiculite, I advise you to remove the clear disc, because it might give mould.
Cover the seeds very thin,or press them a bit in the soil. They are not suitable for winter sowing, they need warm temperatures to germinate (not lower than 70°F)
I collected some Angelonia angustifolia white seeds. They were angular and black, and the size your seeds are in your picture only black.
The seeds I have in the above picture are very flat. These seeds I collected from Angelonia Serena purple. The seeds are smaller and Very Flat.
So, I am wondering if the seeds are so different because one is Angustifolia, and one is Serena.
Anyway, you say the cellophane disc doesn't affect germination. I Did press the seeds onto the soil in order for them to make contact with the moist soil. So, I am guessing that will be sufficient for germination.
My quandry is why the seeds look sooo different.
Edited to say: Thank you for giving me the instructions.
Ribin, Thanks for your reply. I don't think it's Campsis radicans, Trumpetcreeper, I don't have any on the property. I looked at some pictures of the C. r., and I think the C.r. are twice as big in diameter, also the celophane disc of these seeds are really round -- the light gold seed inside is oval but the cellophane disc is really round--not winged.