519846.fig.004a
(a)
519846.fig.004b
(b)
519846.fig.004c
(c)
519846.fig.004d
(d)
Figure 4: Scanning electron micrographs: (a) AP magnified 2,000x, (b) AP 16,000x, (c) CP 1,000x, (d) CP 16,000x.