what are the crosses that appear on the ground pins in a PCB

I am new to PCB designing and I did my first PCB(2 layer) under the guidance of a senior(who is currently unavailable). In that PCB,after
completing the tracking, I had put copper pour on both the top and the bottom layers. This lead to crosses appearing on the pins that were connected to gnd. Even in the actual PCB these crosses are visible. Now when I tried doing the same thing,these crosses did not appear.
Is there any important step that I am missing? I am using Layout plus available in the Orcad 10.0 tool suite.

Those are called thermal reliefs. When you try to solder a pin into a via that connects to a big ground plane, the ground plane will pull away the soldering iron's heat. That means the metals won't get hot enough to wet the solder and make a good solder joint.

By using four thin lines to connect the plated via to the surrounding plane of metal, you retain a conductive path, but increase the thermal resistance (the via can't lose heat to the surrounding flooded plane nearly as fast). Thus, the via, and the pin going through that via, will heat up quickly, the solder will flow, and you'll get a nice, solid solder connection.

To make them, most CAD tools will let you turn on a ground-plane/via option of some kind. Ask your senior person how to do that for your particular program.

Okay, I found out how to attach copper pour to a plane and even got the thermal reliefs. But will it affect the micro-controller's performance if there is a copper pour attached to ground below the crystal?

If I put copper pour around the crystal as recommended in the datasheet and then if I cover the whole top layer with copper pour attached to gnd, the the copper around the crystal disappears. What could be the reason behind this?