diff --git a/casimport/__init__.py b/casimport/__init__.py
index fdde021..ed3e89a 100644
--- a/casimport/__init__.py
+++ b/casimport/__init__.py
@@ -300,7 +300,7 @@ class CASFinder(MetaPathFinder, Loader):
 					if hashurl.scheme == 'hash':
 						break
 				else:
-					raise ValueError('unable to find bash hash url for alias %s' % repr(arg))
+					raise ValueError('unable to find base hash url for alias %s' % repr(arg))
 
 			ms = ModuleSpec(fullname, self, is_package=False,
 			    loader_state=(hashurl,))