What's with all these trades going through at a quarter of a...

What's with all these trades going through at a quarter of a dollar? LNC for instance 110.25 or 110.75... I can't place a buy or sell at these levels, yet trades keep going through even though the buy/sell depth doesn't show them.

Also I sold a parcel of shares at market and a few actually went through at the slightly higher price than the current buy price showed, to my benefit. :/