Chapter 1, The Reptilian Spectacle - UWSpace - University of ...

of the eye, barring developmental anomalies or pathologies. The vascularity of the spectacle was first
documented by Quekett (1852) who hazarded upon it by chance after injecting the vasculature of a
rock python to study a neovascular anomaly of its lens capsule. His illustration is reproduced in Figure
1-4 and shows a complex and apparently irregular meshwork of anastomosing blood vessels with the
degree of anastomosing being greater in the peripheral regions of the spectacle.
Figure 1-4. Earliest known illustration of the
spectacle vasculature, drawn from the injected
vasculature of a rock python (Python molurus).
Reproduced from Quekett 1852.
Quekett’s account seems to have been largely ignored or forgotten, as the next oldest account
of the spectacle vasculature was offered by Ficalbi (1888b), whose neglect in citing Quekett is most
likely due to his being unaware of the earlier author’s work. Ficalbi’s descriptions of the spectacle
vasculature of the snake were also based on injections, by which he demonstrated that the spectacle
dermis is permeated by blood vessels that lie mostly in the posterior region of the dermis and form, as
he described it, an irregularly arranged anastomosing mesh across the whole of the spectacle. His
illustration of the spectacle vasculature of a colubrid (Figure 1-5, next page) showed more precisely
that the entry of the vessels into the spectacle occurs all around its circumference where they form
complex anastomoses before adopting a largely dorso-ventral orientation at the center of the spectacle
with a modest degree of anastomosing. Of interest is the noticeably different vascular layouts between
Ficalbi’s colubrid and Quekett’s pythonid.
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