CEN recently presented a squash mystery (see her comment) - a winter squash medley that's left to the buyer (that's us, to figure out). She sleuthed it out, and identified the butternut variety that she wanted. But I also poked around trying to figure it out too.
I don't know if this was the packet of seeds that she saw, but I happened on to it at a local big box store, and it caught my eye ( I always love a plant mystery).
Sorting them out, there were definitely 4 seed types, but not in the 25% each that were advertised on the packet.
After some time spent looking at squash seed characteristics and images, I figure that the large seeds on the upper left are the acorn squash (a C. pepo variety), the seeds on the right are the spaghetti squash (another C. pepo variety), the seeds on the lower left are the butternut squash (a C. moschata variety), and the two whitish seeds are C. maxima (the Lakota squash).
I could easily be wrong, but this was my best guess!