<正> The mean length of the stria vascularis （SV） and the basilar membrane of four normalguinea pigs measured by means of surface preparation was 21.11 mm and 19. 90 mm respectively

and the mean width of their apical turns of SV and the turns of the cochlear basis was 0. 44 mmand 0. 86 mm respectively. The ultrastructure of SV

spiral ligament （SL） and spiral prominence（SP） of both ears of eight guinea pigs were observed by scanning electron microscopy（SEM） andtransmission electron microsoopy（TEM）. There were a large number of coated vesicles in thesupranuclear region of SV

some opened to the endolymph. A great number of folding cytoplasmicprojections were filled with small vesicles The capillary network was extremely rich indicating thatthe endolymph could be secreted and absorbed by SV. The cellular conjunction in the SV. SL andSP formed an effective barrier. It has not been proved in this study that the melanin offers resistanceto acoustic stimulation.