Medullary ray.

[MIGNAL]

I have a piece of Spruce that shows a fairly distinct medullary ray pattern. At the very end of one of these rays is something that looks like a tiny pin knot. Except I guess it isn't a knot.
Does it have a name? I can't say I've seen this before although it must be a known feature, if somewhat rare.

 

[Chrispy]

Sounds like it could be a resin pocket?

 

[MIGNAL]

Possibly, although it must be one of the smallest resin pockets going. I think it's less than the size of a pin head and certainly no resin in sight. Perhaps it was the very beginnings of a resin pocket?