the smallest femur he had (referable to P. germainepetterae) and the highest estimate, based on comparative data from caviomorph rodents, was for the largest available femur (P. madagascariensis); estimates from primates fell between those extremes. MacPhee favored the lower estimates, because those were based on armadillos, which have femora similar to those of Plesiorycteropus. On the other hand, the caviomorph model produced a better estimate of brain size in Plesiorycteropus. Any of the estimates makes it considerably larger than the largest living tenrec, Tenrec ecaudatus, at up to . The higher estimates would make it larger than any extant native Malagasy mammal. This is consistent with the trend for larger members of the late Pleistocene and Holocene faunas of Madagascar and elsewhere to have been at higher risk of extinction. Skull There are four known skulls (three of P. madagascariensis and one of P. germainepetterae), each of which is damaged. All are missing the front (rostral) part, and three are broken at about the same place (at the paranasal cavities, at the front of the braincase), suggesting that the front part of the skull was thinner and more fragile than the back part, which consists of thick bones. MacPhee estimated maximum skull length in P. madagascariensis at . The length of the frontal bone averages in P. madagascariensis and is in P. germainepetterae. The robust nasal bones, preserved in a single specimen, are widest at the front, a feature unusual among placentals that is also seen in armadillos, and are also unusually flat. The ethmoid labyrinth, in the nasal cavity, was large, suggesting that Plesiorycteropus had a good sense of smell. A much larger part of the nasal septum, which separates the left and right nasal cavities, is ossified than usual in other mammals; MacPhee could find a similar condition only in sloths, which have a very short nose. The lacrimal bone is relatively large. At it is a single lacrimal canal, which opens near the suture between the frontal and lacrimal bones, like in lipotyphlans. There is a small tubercle (absent in aardvarks) near this opening. The orbital cavity, which houses the eyes, is relatively short, similar to the situation in pangolins and armadillos. A distinct tubercle is present on the suture between the frontal and parietal bones in P. germainepetterae, but not P. madagascariensis. P. madagascariensis has a more expansive braincase and a less pronounced narrowing between the