Is there a link between corneal structure and the `corneal cross'?

The `corneal cross', observed when polarised light is reflected from the cornea and viewed through a crossed analyser, has been attributed to the fine anisotropic structure of the cornea causing birefringence or, alternatively, multiple reflections. But when plane polarised light is similarly reflected from isotropic curved surfaces and viewed through a crossed analyser, isogyres are also seen, Moreover, they vanish with a gonioscopic lens neutralising corneal curvature, This suggests that the corneal cross is not a specific attribute of corneal birefringence.