The lamellar structure in the oriented films with and without bandedtexture of a lyotropic aromatic polyamide sheared from the anisotropic solutions hasbeen investigated by mean of'transmission electron microscopy. The lamellar structure of 20 urn in thickness for poly (1

4-phenylene terephthalamide) (PPTA) and of40 urn in thickness for poly (1

4-benzamide) (PBA) was observed. These periodicities of lamellar structure are corresponding to the persistance length of both polymers. The molecular chain is only in extended comformation for these rigid poly-mers. Amodel was suggested to describe the packing arrangement of the molecular chain in the crystalline region of the rigid polymers.