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lenta, R. temporaria, and Hyla arborea. His work forms the 
most complete account of the frog’s skin which has been 
published, which is thus carefully worked out with a view to 
further studying it under pathological conditions. Amongst 
the more remarkable facts recorded are—Ist. The round 
openings or pores between the cells of the epidermis, also 
found passing through the actual substance of epidermic- 
cells, sometimes three through one cell, already observed by 
F. E. Schulze, most of which are the openings of underlying 
unicellular goblet-shaped glands. Eberth regards some as 
mere pores, and suspects the presence of very much finer 
pores in immense numbers. 2nd. The similarly placed open- 
ings of the proper cutaneous glands, which have a curious 
shape, formed by three converging lines like the bite of a leech. 
Srd. The structure of the cutaneous glands, the smooth 
muscle-fibres of which, the areolar tunica propria, and the 
nerve-supply, are described and figured. Of this we have 
given some account below. 4th. The well-known swellings 
which appear on the thumbs of male frogs are carefully 
examined. Eberth cannot find touch-corpuscles nor multi- 
polar ganglion-cells in these organs, as some have described. 
He finds peculiar cells, like white blood-corpuscles, with 
large round nuclei, but does not consider these as nervous 
organs. ‘The cells taken by Ciaccio for multipolar ganglion- 
cells he regards as connective tissue-corpuscles. dth. The 
pigment-cells of the cutis are specially examined. Eberth 
confirms Wittich, as against Briicke, in the conclusion that 
the green colour in the green skin of the back of frogs is 
caused by the covering over of the black pigment-cells by 
yellow pigment-cells, and is not an “ interference-colour,” 
and hence there is not the difference between Hyla and 
Chameleon which Briicke had maintained, for in the former, 
as in the latter, the granules in the pigment-cells which 
appear bluish and yellowish-green by incident light, are 
few and subordinate in effect to the super- and juxta-posi- 
tion of the yellow and black pigment-cells. 6th. The 
fibres in the small papille of the cutis, described by Ciaccio 
as nerves, are shown by Eberth to be smooth muscle-fibres, 
which run perpendicularly and spirally into the papilla. 
The connection of nerve-endings with these muscle-cells is 
described. Instead of ending in connection with the nucleus 
or in its neighbourhood, as recently described by Krause 
for other smooth muscles, in these the muscle-cell tapers 
away to a very long and fine process below, and the nerve- 
fibre joins this long process of the muscle-cell. When the 
medulla oblongata of a frog is cut through there often comes 
