Pin 15 on the IC is actually the pin for Digital Pin 9 (D9) on the Arduino. If you want to see the pinout for the ATmega328 IC, refer the “Pin Mapping” diagram.

On the right hand side there a voltage regulator with smoothing caps. The left side hosts the obligatory pin 13 LED, and the crystal oscillator can be glimpsed on the far side of the ATmega328.