Two crossed falcon feathers.  The name of the crest is Maruni chigai takanoha (丸に違鷹羽) and it belongs to the families Kubo and Hidaka.  There may be other families bearing similar crest.  
The hawk was a symbol of a samurai in old days.
"feather of hawk" was given glory to as the decoration at the time of ceremony such as New Year's Days, and great people of a samurai were able to arrive at one's crown in old days.

That's why it is one of the family crest of arms liked most by a samurai.
Own work
Kace Kaminaga / Kubo Michal