In article . com,
Landtrustlady wrote:
I don't have a photo of this yet, but in December I discovered what
appeared to be a vine growing in a field in MA, a field that had not
been mown in several years. Attached to the vine were several
"mini-loofahs" - i.e., they were loofahs about 1.5 to 2" long. At the
time I found them I thought loofahs were a sea sponge, but I later
discovered they were a gourd. I cannot find any reference to such a
plant with gourds/seedpods that are so small. Has anyone seen this
plant or does anyone know about it? Is it an escapee from a garden?

My guess is Echinocystis lobata, aka Wild Cucumber. It's an annual
vine native to most of the US and southern Canada. AFAIK, it has
no other use than for children to throw the fruits at each other
giggling wildly, since these projectiles have the density of styrofoam
so are not only hard to aim but hit pretty much painlessly. Maybe
children are the natural disseminators of its seeds.

N.B. It's a native plant but can be a fairly invasive weed, so think
twice before growing it in your garden.