Krikštas is a type of gravestone. And this Lutheran semitary is full of them. They used to be made from would rather then a stone. First mentioned in about 16 century they where used in Lithuania minor and Curonian spit. Similar gravestones where also made in Latvia Germany and Swicerland. They used difernent types of wood for female and male gravestones as well as diferent  decoration. taken from: http://lt.wikipedia.org/wiki/Krik%C5%A1tas_%28paminklas%29