I finally decided last night which seeds to start (not all of my iris crosses), and today I divided up some of the seeds from each cross (all 7 seeds from the lowest yielding cross) into little condiment cups with lids. I'll start the stratification later today.
I am using the same sort of labeling scheme as I do with my daylily seedlings. There will be a letter (maybe 2) which is the first letter(s) of the pod parent's name, then 1-2 digits to indicate the particular cross, 2 more digits for the year the seed was harvested, then however many digits to number the seedlings in the cross. (Since I do notes and take images, I want to keep everything straight so all seedlings are now numbered up front, at least with respect to where they are in the row or the window box or whatever. Medium to long term individual labels are only made when and if I keep seedlings for another look.)
So... A1-17-## will be my seedlings from a cross of 'Autumn Thunder' by an old seedling of mine. (It is the only "A" cross this year.)
P1-17-## will be my seedlings from 'Peggy Sue' x 'Ida Red', and P3-17-## will be my seedlings from 'Peggy Sue' x a sibling to 'Love Continues'. (Yes, I also have seeds from a P2-17 cross, but I am probably not going to start those seeds (at least at this time).... I've only got so much room, time, and energy, and I've got daylily seeds to grow too.)