Problem with Esplora: Serial communication

Hi there I am trying to display Information on the serial monitor. I tried out some example codes like EsploraAccelerometer and EsploraLedShow, but the serial monitor stays empty. Too in the LedShow example the Esplora only refreshes its leds all six seconds (or more). I tried out the examples without the serial part, and they worked perfectly, so it is pnly a problem with the seroal, but what can i do?

It would be nice if you could help me :)