Somebody else recently put up a picture of an entire lawn in eastern Canada decorated with these in flower.
I too thought of Puschkinia at first but the structure of them seemed to fit the other. Looking at it today I see the flowers don't have the downward-pointing orientation of Siberian squill.
I see what you mean about downward-pointing flowers on Scilla siberica... all are in full bloom here currently, and, yes, the Scilla siberica point down. Thanks for pointing that out!
Not Puschkinia or Scilla siberica. Its Chionodoxa luciliae. Some do reunite Chionodoxa with Scilla because they will hybridize with Scilla bifolia but the flower structure of Chionodoxa is very different.