Hokoç J N, Cruz E O
J Comp Neurol. 1978 Apr 15;178(4):773-82. doi: 10.1002/cne.901780411.
An electron microscope examination of the optic nerve of the opossum, Didelphis marsupialis aurita, indicates a total count of 74,7000 fibers of which approximately 20% are unmyelinated. The diameters of myelinated fibers ranged from 0.5-7 mum (mode at 1.25 mum) and those of the unmyelinated fibers ranged from 0.25-2.25 mum (mode at 0.75 mum). Myelinated and unmyelinated fibers are uniformly distributed throughout the nerve. Myelin sheath structure is similar to that described in other species and are formed by 2 to 17 myelin rings (mode at 6). There is a good correlation (r = 0.92) between axon and myelin areas. The relation between myelin thickness and axons diameter shows a wide distribution with a peak at 0.77.
对南美负鼠（Didelphis marsupialis aurita）视神经进行的电子显微镜检查表明，其纤维总数为747000条，其中约20%为无髓鞘纤维。有髓鞘纤维的直径范围为0.5 - 7微米（众数为1.25微米），无髓鞘纤维的直径范围为0.25 - 2.25微米（众数为0.75微米）。有髓鞘纤维和无髓鞘纤维在整个神经中均匀分布。髓鞘结构与其他物种中描述的相似，由2至17个髓鞘环形成（众数为6）。轴突面积与髓鞘面积之间存在良好的相关性（r = 0.92）。髓鞘厚度与轴突直径之间的关系分布广泛，峰值出现在0.77处。
