As I understand it Crocus is a genus of 80 plants or so, about 30 of which are cultivated, native to Eurasia and North Africa. Of these the most well known are those varieties which bloom very early in spring--in fact, it is not yet spring, and here they are. A waxy coating protects the parts of the flower from the elements before it blooms. One species of Crocus is cultivated for the production of the spice saffron, made from the dried stigma of the flower. All of this I have learned from the wikipedia entry on Crocuses. Anything more, from the gardeners and cultivated plant fans, would be welcomed in the comments here. I am particularly interested in corrections to the next paragraph, which is educated supposition bordering on bullplop.
I suspect that the pollinators of these flowers did not come over with the bulbs, and that their flowering, while it may cheer the weary winter heart, does nothing to further the plant's reproductive goals. This would be why one does not typically find crocus fruit following the dying of the flower, nor does a North American observer find wild or "volunteer" crocuses grown from seed. Or do they? This photograph shows a crocus growing from between stones, indicating a bizarre or clumsy bulb placement, or perhaps a wandering plant. Many plants, including snowdrop, spread vegetatively in the dirt, so that flowers may emerge some distance from the original bulb planting. The question still bothers me: does crocus participate in the ecosystem in any meaningful way, or is it just a pleasant reminder of spring, placed by conscientious gardeners?