C/U White marking on Acer poss egg?

C/U White marking on Acer poss egg?

Observation - C/U White marking on Acer poss egg?. Description: Not sure perhaps the egg/remnants of some insect? Saw many dots of white slightly furry raised lumps, which by time I took picture on a very wet day appeared to be flat and empty. Could see no sign of any insect living on Acer and tree appears undamaged b

Not sure perhaps the egg/remnants of some insect? Saw many dots of white slightly furry raised lumps, which by time I took picture on a very wet day appeared to be flat and empty. Could see no sign of any insect living on Acer and tree appears undamaged but would like to identify source if possible?