" Under this power the bead-like appearance, noticed with the sim-
ple lens, resolved itself into a definite form, resembling precisely the
cells of the honeycomb as they appear on the broad plane. Like theso
cells, each division was hexagonal. The substance of each division
was convex exteriorly. We are reminded that this is the form which
economizes space the most, and that it is also the form always taken
by the equal sized round bodies when equally pressed together. This
law we see exemplified in the cellular tissue oi plants, and we account
for the elongated fonn of the cells of the fibrous tissue, by unequal pres-
sure. We see this law in the formation of the cells of the honeycomb,
as equally sized globular cells equally pressed laierdHy^ ^^^ forming
bexaffonal cells. We see it agam, though imperfectly, it is true, in
soap-bubbles. Mght we not, therefore, infer that this peculiar form is
the natural effect of a known law, and that it could not assume any
other form ? But to remove all doubt, we must prove our premises,
that is, if the facets of an insect's eye, composed originally of an im-
mense number of spheres of equal size, equally pressed, laterally, pass
into the hexa^nal form, or suffer any other modification. That tney
are of equal size is manifest fi*om simple inspection.
** We will now see if experiments prove they are, or have been,
spheres ; but I must first speak of some further examination of the
cornea. I counted the number of facets, or faces, by the microme-
ter, and found in. each eye 12,500, but I think they are somewhat more
numerous. Around each facet I found a fringe of fine hairs which
teem to fulfil the purpose of eyelashes.
