diff --git a/zipline/data/bundles/csvdir.py b/zipline/data/bundles/csvdir.py
index 0418c9ec90..22aeedd146 100644
--- a/zipline/data/bundles/csvdir.py
+++ b/zipline/data/bundles/csvdir.py
@@ -175,12 +175,10 @@ def _pricing_iter(csvdir, symbols, metadata, divs_splits, show_progress):
         for sid, symbol in enumerate(it):
             logger.debug('%s: sid %s' % (symbol, sid))
 
-            try:
-                fname = [fname for fname in files
-                         if '%s.csv' % symbol in fname][0]
-            except IndexError:
-                raise ValueError("%s.csv file is not in %s" % (symbol, csvdir))
-
+            fname = symbol + '.csv'
+            if fname not in files:
+                raise ValueError("%s.csv file is not in %s" % (symbol, csvdir)) 
+                
             dfr = read_csv(os.path.join(csvdir, fname),
                            parse_dates=[0],
                            infer_datetime_format=True,