Magnetic resonance imaging and three-dimensional reconstructions of the brain of a fetal common dolphin, Delphinus delphis

To demonstrate the kinds of data that can be obtained non-destructively and non-invasively from preserved museum specimens using modern imaging techno logy the head region of a whole body fetal specimen of the common dolphin, Delphinus delphis, aged 8-9 months post-conception, was scanned using Magne tic Resonance Imaging (MRI). Series of scans were obtained in coronal, sagi ttal and horizontal planes. A digital three-dimensional reconstruction of t he whole brain was prepared from the coronal series of scans. Sectional are as and three-dimensional volumes were obtained of the cerebral hemispheres and of the brainstem-plus-cerebellum. Neuroanatomical features identified i n the scans include the major sulci of the cerebral hemispheres, well-diffe rentiated regions of gray and white matter, the mesencephalic, pontine, and cervical flexures, the "foreshortened" appearance of the forebrain, and th e large auditory inferior colliculi. These findings show that numerous feat ures of the fetal common dolphin brain can be visualized and analyzed from MRI scans.