Nature's Hand. Leitz Elmar-V 65mm, Bellows II

Electricians have been working over the last few days to install new lighting fixtures in the driveway and parking lot of our building.  On my way in this evening I stopped to inspect the work and how the fixtures had been attached to their concrete footings.  As I was bending down at ground level I noticed this strange artifact which, at first glance appeared to be part of a wasp nest.  But there were no inhabitants, and the object seems to be of fibrous vegetable matter rather than wax.  Having made quite sure that nobody was living there I brought it upstairs to be photographed in "laboratory conditions".  Each little hexagonal cell is about 4.5mm across.  I think it's a seed pod of some kind, and welcome suggestions.

Thanks for confirming the wasp nest theory, everybody!