diff --git a/src/alu3dgrid_serial.h b/src/alu3dgrid_serial.h
index da5ad3bbd2c11d5ae505a929eb4629a53c85afc7..a2ff99bff7eccf1215ae6a950e3d253865a6ee10 100644
--- a/src/alu3dgrid_serial.h
+++ b/src/alu3dgrid_serial.h
@@ -9,7 +9,7 @@
 
 namespace ALU3dGridSpace {
 
-typedef enum {hexa,tetra} grid_t;
+typedef enum ALUElementType { hexa , tetra , hexa_periodic , tetra_periodic } grid_t;
 
 struct GatherScatter;
 typedef GatherScatter GatherScatterType;