Fig. 12. Bivariate comparison of two dental proportions discussed in the text, with illustrated examples of contrasting morphologies. Closed curves delimit sets of taxa assigned to alternative states of character 57. Taxon labels: 1, Caluromys lanatus; 2, Caluromys philander; 3, Caluromysiops irrupta; 4, Chironectes minimus; 5, Didelphis albiventris; 6, Didelphis marsupialis; 7, Didelphis virginiana; 8, Glironia venusta; 9, Gracilinanus microtarsus; 10, Lestodelphys halli; 11, Lutreolina crassicaudata; 12, Marmosa canescens; 13, Marmosa lepida; 14, Marmosa mexicana; 15, Marmosa murina; 16, Marmosa robinsoni; 17, Marmosa rubra; 18, Marmosops impavidus; 19, Marmosops incanus; 20, Marmosops noctivagus; 21, Marmosops parvidens; 22, Marmosops pinheiroi; 23, Metachirus nudicaudatus; 24, Micoureus demerarae; 25, Micoureus paraguayanus; 26, Micoureus regina; 27, Monodelphis adusta; 28, Monodelphis brevicaudata; 29, Monodelphis emiliae; 30, Monodelphis theresa; 31, Philander frenata; 32, Philander mcilhennyi; 33, Philander opossum; 34, Thylamys pallidior; 35, Thylamys venustus. Other labels: MC, metacrista; PC, postprotocrista.