Maverick County Courthouse, Eagle Pass, Texas 188/254 âThe Rio Grande forms Maverick Countyâs western and international border with Mexico; the county is bordered on the north by Kinney County, on the east by Zavala County, and on the south by Webb County.
The function of the optic chiasma  is to relay electric signals as they pas â¦ s from the optic nerve to  the brain.
Within the middle cranial fossa, the optic nerves from each eye unite to form the optic chiasm. At the chiasm, fibres from the nasal (medial) half of each retina cross over, forming the optic tracts: Left optic tract â contains fibres from the left temporal (lateral) retina, and the right nasal (medial) retina.