Overall examination of the corresponding data reveals
that the morphological parameters are not the same even
between the two stemmata of the same individual, suggesting
that these are residual differences that may be within
unavoidable measurement errors. The radius of the innercurvature of the corneal lens (ri) is always smaller when
measured from sections than it is in wholemount observations.
This may result from some difficulty in identifying
the boundary of the lens in sections (see Section 4). Since
a larger ri would require a higher refractive index of the
corneal lens (n1) in order to achieve a given focal length,
this difference would result in larger n1 in wholemount
observation than in sections in all individuals except Specimen
10 in Table 3. Apparent refractive indices n1 are calculated
down to the second decimal place in Table 3.
However, considering the errors in measurements of both
morphology and optics, only the first decimal place may
be valid. Thus, it can be said that the apparent refractive
index n1 is around 1.8.