This was in a residential garden in Toronto. Going from memory, i believe the size was approx. 2 1/2" to 3" in diamater.
Looks to me like an allium, but you'll find many of these look quite similar at this stage, I doubt you can get much further than that. See for example a Google image search for allium+flower+seeds (added 'seeds' to the search to get later stages like the one you've got).
Alliums include onions and garlic (both cultivated versions you'd commonly find in a grocery store and wild varieties; for onions this includes green onions and scallions as well as bulb onions), numerous other plants grown primarily for decorative purposes commonly called "allium", and lots of other wild plants.
I agree with @BryanKrause that this is an Allium seed head. The seed pod and seed on the end give it away
For another partial match from a commonly cultivated plant in domestic gardens, Agapanthus seed heads look similar, though the seed pod and seeds are elongated and winged. When these dehisce at the end of seeding you can be left with a head that superficially looks like OP's photo, but without the small black seeds. Agapanthus tend to be much larger, up to about 6 inches (15 cm) across, though there are many cultivars, some of which have smaller inflorescences.
Head with seed pods (from gardeningknowhow.com, photo by eldadcarin):
Without pods (from seenobjects.org, photo by Martin Kenny):