RADIATION

n. Rad-i2-a'sh'n. ~L .,radiatio. Fr.,r.,rai/onnement. Ger., R., Strahlung. 1. Divergence in ray-like lines from a central point (said especially of light and heat). 2. Any structure presenting the appearance of radiating lines, fa, 48.]- Optical r's, Optic r. [Gratiolet]. Fr., faisceau du pulvinar. Ger., Sehstrahlung. A bundle of nerve-fibres in the posterior part of the optic thalamus, continuous with those of the corona radiata. probably the termination of the optic nerve. The fibres are derived mostly from the optic tract and the external and internal geniculate bodies, and radiate into the parietal and occipital lobes. [1, 17, 28 (K); "Med. Rec.," Nov. 1, 1884, p. 477 (K).] R. der Zwirbel (Ger.). Of Treviranus, probably the connection of the peduncles U2, blue; U3, lull; U4, full; U6, urn; IJ 6, like u (German). [s. 377]