Cnidae of Macrodactyla aspera. A, spirocyst. B, small basitrich. C,
basitrich. D, large basitrich. E, small basitrich. F, basitrich. G, small basitrich.
H, basitrich. I, small basitrich. J, large basitrich. K, wide basitrich. L, small
basitrich. M, large basitrich. N, wide basitrich. O, microbasic
p-mastigophore. Scale bar = 10 μm. Refer to table 2 for key to
letters.