Synechococcus (strain WH8113). (OMi) and a patch of the inner leaflet of cell membrane (CMi) where the outer membrane has been pulled away. Typical of such outer membrane fractures, a profusion of spicules lie about the perimeter or lie flat along the outer membrane surface. Consideration of the fracture process explains the disposition of these spicules. If the spicules are tightly rooted to their bases, and the bond energy of their composition exceeds that of the interaction between their surfaces and the ambient ice, then the spicules would be pulled out of the frozen material that is cleaved away by the knife fracture, and would then fall onto the newly exposed surface thereby demonstrating their original continuity with it. Differences in angles of cleavage may explain the relative sparseness of the spicules on the top of the exposed surface compared to the edges. Scale bar, 100 nm.