The stripe down the middle is a bit baffling but I'll offer Ornithogalum and Ismene, as starters. Possibly Hippeastrum, but that could be stretching it.

could it be blue bells? hyacinthoides? here is a link,
bye, Lin

http://www.srgc.org.uk/bulblog/log2008/290508/log.html

Here is a link that might be useful: blue bells

Don't think they're Spanish bluebells because those do flop over and the OP says these don't. They are definitely not English bluebells which have much finer foliage and smaller bulbs.

My guess is Lycoris Radiata. The white stripe down the middle of the foliage is an extremely good clue. The bulb size, shape, and color is right too. I hesitate a bit, as the foliage looks broader than normal. On the other hand, my luteas (yellow blooms) have broader foliage than the red ones, so that could well be what you have.

It is possible that it is some variety of crinum. Ellen Bosanquet is not an extremely large bulb, or plant, and does offset. It is quite common, so that would be a possibility. However, this time of year all my crinums have died back to the ground and there is nothing but brown, dried ick over their tops. Hannibal's Dwarf is another possibility, sizewise.

Hippeastrum have died entirely back to the ground too by now, so that's not likely either. And, your foliage is all wrong for amaryllis.

Right now, in my yard, here are the bulbs that have standing green foliage: Lycoris Radiata, Lycoris lutea, Narcissus of all kinds (no white stripes), Rhodophiala (your foliage is far broader), Leucojum (you're further south, so this might be it), Dutch Iris (your foliage is too broad).

Clear as mud, right? The only way to know for certain is to plant them and wait for them to bloom.

I, for one, would be interested in your results....