what would you do?

My child has had so many run ins with the same kid, name calling/teasing/what not. They are in preschool, and I rarely hear about these happenings from the teachers (my child tells me), and I know they see/hear it because they tell her to use her words and if it doesn't stop to just ignore him (sure makes sense if they weren't in the same class and he wasn't relentless). Well last week I found out that he wouldn't leave her alone when she was in the book space reading, and he kept shoving his book in her face, she told him to stop several times and was trying to ignore him but then he spit in her face! 
I received no note, no incident report form, no nothing. I find out later on from the other person who works in the room (friend of mine, she says he was put in timeout but no mention of it to his mom or I), I am getting second hand stories from her and my child and I'm annoyed I received NOTHING from her teacher and she said no one helped her clean her face off or anything. 
There's only a month left of school so I don't want to make this too big of an issue but what would you do??
**edit I have talked to the teachers, both of them, the one agrees with me but she's the assistant and has little to no pull, and the other makes excuses for him and she actually told my daughter that sometimes when boys like us they are mean to us.  I've also emailed them asking for an explainationcabout what happened and why I was not told anything about it**