The osteological terminology used here follows Baumel et al. (1993) but terms are translated into English. Measure− ments were taken after von den Driesch (1976) and Stephan (1979). For metrical comparisons, using published data, it has to be considered that different authors (e.g., Simpson 1946, 1975b, 1979a, b), had slightly deviating ways of mea− suring the greatest lengths of some limb bones; often they measured the functional lengths, taking recessed points or sulci between condyles (e.g., for femur, distal tibiotarsus, distal tarsometatarsus) as landmarks. However, the differ− ences in the values are never more than a few mm.
The penguin material of Cerro la Bruja described here co− mes from excavations of Christian de Muizon and belongs to MNHN, but is temporarily housed in the collections of UCBL. For morphological comparisons with the fossil Chil− ean species, Spheniscus chilensis, parts of the paratype mate− rial (UF 143295, 143299, 144112, 144134, 144148, 144149, 144154, 144168, 144169) were at disposal by loan. Morpho− logical comparisons with extant penguins are based on fol− lowing specimens provided by the collections of SAPM and UCBL: Spheniscus humboldti (SAPM 5 male, 12 female; UCBL 25588), S. demersus (SAPM 12 male, 13 female), S. magellanicus (SAPM 8 male, 9 female), Eudyptes chrysochome (junior synonym E. crestatus), (SAPM 6 male, 5 female), E. chrysolophus (SAPM 1 ?), Aptenodytes patagonicus (SAPM 6 male, 8 female), Pygoscelis papua (SAPM 12 male, 3 female), and Py. adeliae (UCBL XII 1978). Metric data of extant penguin species were acquired on the aforementioned specimens as well as additional material from the SAPM. Measurements of S. mendiculus are based on specimens at the LACM and were provided by Kenneth Campbell.