diff --git a/IPython/frontend/html/notebook/notebookapp.py b/IPython/frontend/html/notebook/notebookapp.py
index 1a9dbcb..9a0cbfe 100644
--- a/IPython/frontend/html/notebook/notebookapp.py
+++ b/IPython/frontend/html/notebook/notebookapp.py
@@ -545,10 +545,10 @@ class NotebookApp(BaseIPythonApplication):
         if not self.ip:
             warning = "WARNING: The notebook server is listening on all IP addresses"
             if ssl_options is None:
-                self.log.critical(warning + " and not using encryption. This"
+                self.log.critical(warning + " and not using encryption. This "
                     "is not recommended.")
             if not self.password and not self.read_only:
-                self.log.critical(warning + "and not using authentication."
+                self.log.critical(warning + " and not using authentication. "
                     "This is highly insecure and not recommended.")
         success = None
         for port in random_ports(self.port, self.port_retries+1):