You are very lucky to have been given so many seeds, David. Forget the heat bench, Erythronium do not need it. The seeds would have been better being sown last summer, as soon as ripe, so will now need to be soaked for 24 hours before sowing and the container left outside exposed to all weathers. For detailed information I would suggest opening this link to an article by one of Scotland's most skilled bulb growers, Ian Young.
http://www.srgc.org.uk/journal/young/bulbsfromseed.html

Great minds think alike, Bulbaholic!! Interesting web link too, especially the bit about soaking with soap to break the surface water tension ... thank you davidwadland for asking the question. Hope your answer is answered?!

Many thanks to you both I'll take your advice. Davidwadland.