tapetum

[Mod. Lat., from Lat. tapete =a carpet, tapestry.] 1. Anat .: Certain cro fibers of the corpus cal losum spreading outward on the roof of the lateral ventricles of the cerebrum. 2. Compar . Anat .: A shining spot on the outside of the optic nerve in the eyes of certain animals, which is owing to the absence of the pig mentum nigrum occasioning the reflection of a portion of the rays from the membrana ruyschiana . Its use appears to be to cause a double impre ion on the retina, and thus add to the intensity of vision. It may be observed distinctly in the eye of the common cat.