Swellesley reader BelindaH sent us this freaky photo of what I first thought were skulls, but are actually some sort of fungi, behind the tennis course near Sprague Field. (Reader MC suggests the growths are Giant Puffballs.)
Truffle, a standard poodle, provides some perspective above on their size.
And here’s another one, found at Boulder Brook Reservation in Wellesley that discoverer DennyN says is the size of a volleyball.
These are giant puffballs. They are edible when young (when the spore mass inside is white throughout). They turn brown with maturity.
Giant puffballs are often sliced and fried and used as a bread or pizza crust substitute.