minor fix to test_bartlett
minor fix to test_bartlett

jcpeterson/Dallinger,berkeley-cocosci/Wallace,jcpeterson/Dallinger,berkeley-cocosci/Wallace,jcpeterson/Dallinger,suchow/Wallace,berkeley-cocosci/Wallace,jcpeterson/Dallinger,Dallinger/Dallinger,Dallinger/Dallinger,Dallinger/Dallinger,Dallinger/Dallinger,Dallinger/Dallinger,suchow/Wallace,suchow/Wallace,jcpeterson/Dallinger