Papaver somniferum, breadseed poppies. These are also commonly called opium poppies as they are the source of the narcotic which is used to manufacture heroin. Although seldom enforced, it is technically illegal to grow these, so many vendors do not advertise the species very pronouncedly. Oddly, the seeds themselves are not illegal, as they are the commonly used in baking.

btw, you'd have to grow several acres of these poppies to generate any appreciable amount of opium, which is why they tend get overlooked when grown as ornamentals in a garden.

"Papaver spp" "various species of poppy": the abbreviation spp means species, plural. So it's a mixture.