simple papillaj, buried under a common investment of scaly epithelium, that differs
from the cuticle only in its greater tenuity and moistness. On the removal of this
delicate epithelium by maceration, the papillae stand out free from the membrane,
and are seen to consist of an envelope of basement membrane, enclosing a paren-
chyma obscurely granular, with the capillary loop already mentioned. After much



Vertical aection of one of the ctKnunvallate
papillas: — a. Central part. 6, 6, Border, c, c,
FissDre between centre and border. Tlie
Becondary papillie are seen covered by the
epithelium. Similar papillae are seen, d, d, on
the membrane beyond. HagniGed 8 diameters.
care, we have not been able to see nervous tubules within them ; but they must
exist under some important modification, which most probably consists in the
absence of their characteristic white substance of Schwann. These simple papiUsB
are represented in fig. 95.
The circumvallate papillce (fig. 94, a, and fig. 96) consist of a central flattened




, Compound papilla on the side of the
foramen cncum, injected : — a, a, Arterial
tmga. o, V, VeinB. The capillary loopa
indicate the simple papillte; in one of
which, 6, the injected matter has been
extr&w«ated within the basement mem-
brane of the papilla, the outline of which
is thoB distingoiBhed. c, Capillary plexus,
where no papilles exist, e, e, External
surface of the epithelium of the papilla.
Magnified 15 diameters.
, One of tbe simple papilln of k.:-~-
a, V, V, Arterial and Tenons sides of the
capillary loops, b, b. Basement mem-
brane, d, Deeper epithelial particles
resting on the basement membrane.
*, Scaly epithelium on tbe surface.
Magnified 300 diameters.
