Fig. 1.

(A) An adult galago (O. garnetti). (B) A simplified diagram of the trigeminal somatosensory lemniscal pathway. (C and D) Cleared skin samples of the upper (C) and lower (D) face reveal the blood sinuses of vibrissae. The white arrow in C points to an asymmetrically present blood sinus. (E) Schematic of one side of a galago face indicating the mystacial, mandibular, and maxillary vibrissae. (F) A transverse section of the flattened skin of the face stained for hematoxylin and eosin showing the blood sinuses and innervation of a vibrissae follicle. The arrowhead indicates a blood sinus; arrows indicate nerves innervating the follicle. (Scale bar: 500 µm.) 3b, primate primary somatosensory cortex; STN, spinal trigeminal nucleus; TG, trigeminal ganglion; VPM, ventroposterior medial subnucleus of the thalamus.