关键词: 白暨豚, 脊髓, 细胞构筑, 脊髓背索核

Abstract: The spinal cord from two adult females of Lipotes vexillifer was available for study．Frozen sections of the spinal cord of one animals were cut at l0 μm ，20 μm and 30μm respectively，and stained with 1％ thionine，Klüver FB—CVdouble staining or by silvering．Paraffin sections of T2 and Lc₁ were propared for comparison．Thirty pairs of the spinal nerves were counted in the gross anatomy in both of the specimens.
The descriptive formula of the spinal cord of Lipotes vexillifer was C₈-- T₁₀- L_c12. The gray matter was divided into 10 layers according to the Rexed's Principle of the laminar cyloarchitecture pattern of spinal cord.The relationship between each of the layers and the corresponding nucleus was described．Groups of special cells were found in the lateral funiculus,dorsal funiculus and ventral funiculus of the while matter in Lipotes．But the special cell groups in the lateral funiculus in Neophocaena were found in the thoracic segments and lumbocaudal segments and were referred to lateral thoracic nucleus and lateral lumbocaudal nucleus respectively．In Lipote，these cells groups were found in the whole length of the lateral funiculus including the cervical segments．Therefore，They were referred to lateral cervical nucleus，lateral thoracic nucleus and Lateral lumbocaudal nucleus respectively. The speciaI cell groups found in the dorsal funiculus were referred to spino-dorsal-funiculus nucleus．The pia matter invaginated in the spinal cord proper and forming cavities and canals in white matter and gray rttalter．The cavities and canals were filled with cerebrospinal fluid in which the nerve cells were immersed.
These cells were believed to be cerebrospinal fluid—contacting neurons(DSF—CN) and will be discussed in detail in another paper．

Key words: Lipotes vexittiffr, Spinal cord, Cytoarchitecture, Spino-dorsal-funiculus nucleus(NSDF)