54 _ A. B. MAOALLUM. 
They are present during larval life only, and appear first in 
tadpoles of 33 cm. length. The refracting, colloid substance 
ot which they are formed is not easily attacked by reagents, 
but various colouring matters stain it quickly. They are 
apparently wholly absent from the cells of the superficial layer 
of the epithelium, and when occurring in those of the basal 
layer they rest with an expanded foot on the corium. They 
are easily isolated from the cells containing them, and if the 
epithelium is brushed away, many of them are found to be 
attached to the corium. Their shape varies greatly, being 
sometimes fusiform, sometimes rodlike or-fibrous, and at other 
times resembling ciosed, or open rings, or spherical masses. 
Some of the elongated or rodlike forms appeared to be consti- 
tuted of a central axis and a more refracting sheath. 
Eberth at first considered these structures to be intracellular 
nerve terminations, but on subjecting them to the action of 
gold chloride could find no nerve-fibrils connected with them. 
As to their significance he could give no definite opinion other 
than that they are secretions of the protoplasm which arise first 
in the immediate neighbourhood of the nucleus. 
Leydig! has recently described these structures, now termed 
the figures of Eberth, as they occur in the skin of the larvee of 
Hyla arborea and Pelobates fuscus, and has put forward 
the view that they are comparable to the fusiform bodies in the 
cutaneous gland cells of certain Gasteropods or to the urticating 
threads in Celenterates. 
To return to nerve terminations proper. Klein? has given 
a description of the distribution of peripheral nerve-fibres in 
the tail of the tadpole of Hyla. He found a plexus of non- 
medullated fibres situated below the corium, and giving rise to 
finer fibres, which, approaching the epithelium, anastomose 
1 «Neue Beitrage zur anatomischen Kenntniss der Hautdecke und Haut- 
sinnesorgane der Fische.” (‘Sonderabdruck aus der Festschrift der Natur- 
forschenden Gesellschaft zu Halle,’ Halle, 1879.) 
* «Handbook for the Physiological Laboratory,’ 1873, p. 80. I have not, 
unfortunately, access at present to the important work by the same author, of 
which the paragraph in the Handbook is evidently but a short abstract. 
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