Legislative Power and Sovereignty

Systematics of the South American marsupial family Microbiotheriidae / Larry G. Marshall --.

“…Secondly, Ameghino may have taken it with him to the MACN when he resigned from his post at the MLP. This had been shown to be the case for other type and referred specimens described by Ameghino in 1887 (see Marshall, 1980, p. 36n), and it could well be the case with M. tehuelchum. There is one specimen in the Ameghino collection in the MACN (MACN 1) which is labeled "tipo" of M. tehuelchum and is listed as being collected from Santa Cruz.…”

“…Lectotype of P. gracilis. -MACN 8457, a fragment of a left mandibular ramus with P3-M3 complete (selected lectotype and figured by Reig, 1955b, p. 64, fig. 2; and Marshall, 1980, fig. 7).…”

“…6.4 mm Altura de la mandfbula debajo del alveolo de Pm 3 2.5 mm Altura de la mandfbula debajo de M 4 3.5 mm In Ameghino's description of this species he records the presence of a large alveolus at the anterior end of the jaw which he regards as for an incisor and which he envisions further to be as large and procumbent as in species of the caenolestid genera Abderites, Acdestis, and Epanorthus ( = Palaeothentes, see Marshall, 1980). As shown in Ringuelet's figure of this specimen (pi.…”

“…Winge (1923 [1941]) placed Microbiotherium in a new tribe Microbiotheriini in the family Epanorthidae ( = Caenolestidae; see Marshall, 1980). He characterized the genus and tribe as having a typical didelphid dental formula of J:}:^:|.…”

“…This confusion was the result of similarities in lower molar morphology of fossil caenolestids here referred to the species Stilotherium dissimile and Phonocdromus gracilis and the microbiothere species Microbiotherium patagonicum and M. tehuelchum (see below). These similarities were responsible for Ameghino's (1887) initial referral of Stilotherium dissimile to the Microbiotheriidae, although he soon realized this error and in 1891 removed Stilotherium to the family Garzonidae ( = Caenolestidae) where it clearly belongs (Marshall, 1980). A detailed comparison of the dentition of Stilotherium dissimile with microbiotheres is presented by Pascual & Herrera (1975), a study made with consideration of the didelphid-caenolestid dichotomy.…”