diff -u b/facetapi_select.module b/facetapi_select.module
--- b/facetapi_select.module
+++ b/facetapi_select.module
@@ -100,7 +100,7 @@
 
     // We keep track of how many facets we're adding, because each facet form
     // needs a different form id.
-    if (end($options) !== '(-)') {
+    if (end($variables['options']) !== '(-)') {
       if (!isset($form_state)) {
         $form_state = array();
       }