diff --git a/src/fix_adapt.cpp b/src/fix_adapt.cpp
index 701e16ad6d..83ffe62cec 100644
--- a/src/fix_adapt.cpp
+++ b/src/fix_adapt.cpp
@@ -86,8 +86,8 @@ FixAdapt::FixAdapt(LAMMPS *lmp, int narg, char **arg) : Fix(lmp, narg, arg)
       strcpy(param[nadapt],arg[iarg+2]);
       force->bounds(arg[iarg+3],atom->ntypes,ilo[nadapt],ihi[nadapt]);
       force->bounds(arg[iarg+4],atom->ntypes,jlo[nadapt],jhi[nadapt]);
-      if (strstr(arg[iarg+5],"v_") == arg[iarg+1]) {
-	n = strlen(&arg[iarg+1][2]) + 1;
+      if (strstr(arg[iarg+5],"v_") == arg[iarg+5]) {
+	n = strlen(&arg[iarg+5][2]) + 1;
 	var[nadapt] = new char[n];
 	strcpy(var[nadapt],&arg[iarg+5][2]);
       } else error->all("Illegal fix adapt command");
@@ -99,8 +99,8 @@ FixAdapt::FixAdapt(LAMMPS *lmp, int narg, char **arg) : Fix(lmp, narg, arg)
       int n = strlen(arg[iarg+1]) + 1;
       param[nadapt] = new char[n];
       strcpy(param[nadapt],arg[iarg+1]);
-      if (strstr(arg[iarg+2],"v_") == arg[iarg+1]) {
-	n = strlen(&arg[iarg+1][2]) + 1;
+      if (strstr(arg[iarg+2],"v_") == arg[iarg+2]) {
+	n = strlen(&arg[iarg+2][2]) + 1;
 	var[nadapt] = new char[n];
 	strcpy(var[nadapt],&arg[iarg+2][2]);
       } else error->all("Illegal fix adapt command");