diff -up src/sage/graphs/graph_generators.py.orig src/sage/graphs/graph_generators.py
--- src/sage/graphs/graph_generators.py.orig	2015-07-26 07:34:43.000000000 -0600
+++ src/sage/graphs/graph_generators.py	2016-04-28 21:13:15.214276462 -0600
@@ -841,7 +841,7 @@ class GraphGenerators():
         from sage.misc.package import is_package_installed
         if not is_package_installed("nauty"):
             raise TypeError("the optional nauty package is not installed")
-        sp = subprocess.Popen("geng {0}".format(options), shell=True,
+        sp = subprocess.Popen("nauty-geng {0}".format(options), shell=True,
                               stdin=subprocess.PIPE, stdout=subprocess.PIPE,
                               stderr=subprocess.PIPE, close_fds=True)
         if debug: