Incidence of Bilateral Anterior Venæ Cavæ in a series of Eutherian Fœtuses



  • 1We present a survey of the literature on the occurrence of bilateral anterior venæ cavæ in mammals. In some they are to be regarded as normal, in others as exceptional.
  • 2We ourselves have found bilateral anterior vanæ cavæ in two red kangaroos, two Bennett's wallabies, one African elephant, and one Indian fruit-bat; in all these animals they are to be regarded as normal. We have also found them in a lion and a brown capuchin monkey; in these animals they are to be regarded as exceptional.
  • 3In agreement with the observation made by Forbes (1881), we report the occurrence of a single A.V.C. in a specimen of the short-headed fiying-opossum (Petaurus breviceps Waterh.), an exception to Owen's generalization that all marsupials have bilateral anterior venæ cavæ.