The pretectal olivary nucleus of the cat: evidence for a two-tailed structure

The pretectal olivary nucleus of the cat was reconstructed from Nissl and myelin stained tissue. The olivary nucleus is found to have a medially placed head region and two tail regions which extend obliquely from the head region. The retino-olivary projection was also analyzed using the anterograde autoradiographic tracing method. Retinal input is found bilaterally over both the head of the nucleus and the tail regions. The distribution of silver grains, when compared bilaterally, appears slightly more dense over the contralateral nucleus.