Stuck with:
5A PB boy? Not old,9 (4) and 9 is HARE
6D Reptiles (8) ??A???R?
13A Java Man (5) I???S
15D Devices in PR if 31? (8) ?R?N???? and 31 is RESTLESS
5A BP (not PB) is Baden Powell
6D answer is related to how they might move
13A double definition
15D if an anagram of the answer is "rest"-less you're left with " in PR"