TRANSACTIONS OF MICROSCOPICAL SOCIETY. 
DESCRIPTION OF PLATES IV & V, 
Illustrating Dr. Ciaccio's paper on tlie Distribution of 
Nerves to the Skin of the Frog, with Physiological Re- 
marks on the Ganglia connected with the Cerebro- Spinal 
Nerve. 
Fig. 
1. — Perpendicular section of the skin of the frog : a, outer layer ; h, inner 
layer ; <?, outer layer ; d, middle layer ; (?, inner layer ; bundles 
of dark-bordered nerve-fibres ; g, capillary vessels ; \ nuclei of 
middle layer ; mucous glands ; connective tissue between the 
superficial capillary vessels and the inner layer of the epidermis ; 
I, fine fibres of elongated tissue. 
2. — Division and subdivision of tlie bundles of dark-bordered fibres dis- 
tributed to the inner layer of the derma of the frog. Tlie bundles 
unite with one another in such a manner as to form a network, 
with meshes varying in size and shape. The nervous network is 
interlaced with that of the capillaries. In the drawing are also 
represented some branched cells of greenish pigment, and fine 
elastic fibres connected with nuclei. This kind of fine elastic tis- 
sue abounds in this layer, x 120. 
3. — Pine nerve-fibres with one dark-bordered fibre, which divides and ter- 
minates in pale fibres. The fine nerve-fibres ramifying in the 
sheath, and the pale fibres in continuation with the dark- bordered 
fibres, very near the surface of the derma, mingle together and 
form bundles, which, in their course branch and pass to different 
distributions. Here may be seen two fine branches, distributed to 
one of those glands which exists in considerable number in this 
layer. The nuclei, which are, here and there, observed in the 
drawing, are the nuclei of development of the pigment-cells. From 
the outer layer of the derma, x 425. 
4. — Terminal bundles of pale fibres continuous with dark-bordered fibres, 
which are not represented in the figure. The bundles are seen to 
divide and subdivide, and interchange their respective fibres. 
They form a plexus, which lies immediately beneath the capillaries. 
The fibres composing the bundles do not exhibit any of those 
spindle-shaped swellings which are so frequently observed in the 
nerve-fibres which run in the same sheath with the dark-bordered 
fibres, or with the capillary vessels. From the outer layer of the 
derma, seen from below. X 540. 
5. — Transverse section of the middle layer of the derma : — A. Bundles of 
dark-bordered fibres cut across. B. Small bundles of fine fibres 
emerging from the sheath of the dark-bordered fibres. The bun- 
dle, on its way, is seen to divide and subdivide, and to be connected 
