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epidermis covering the nose of the common mole. The organ 
is seen by the naked eye to be covered with minute dots, 
which are in reality papille, and each of these contains the 
peculiar nervous structure described as an organ of touch. 
The papilla consists of a dome-shaped elevation, involving 
the mucous layer as well as the external layer of epidermis, 
and projecting a little into the true skin. In its centre is a 
nearly cylindrical or hour-shaped cavity forming an epidermic 
-tube, in which is contained a structureless mass of connec- 
tive tissue, imbedding nerve-fibres. This is the organ of 
touch. To the lower end of each of these passes a bundle of 
about twenty medullated nerve-fibres, proceeding from the 
extremely rich nerve-supply of the true skin. On entering 
the touch organ the fibres lose their sheath, and pass 
onwards as simple “axis cylinders.” Most of them are 
symmetrically arranged in a ring, while two or three are 
centrally situated. The outer part of the epidermic tube 
containing this structure is composed of very regular layers of 
epidermic cells, and each of the finest nerve-fibres as it passes 
these is attached to the cell by a nodule about four lines its 
own diameter. The nodules thus form a series of very 
symmetrical rings. This arrangement is continued till about 
the fourth or fifth epidermic ring from the surface, beyond 
which the tube appears to be empty. Some quite isolated 
“axis cylinders” were also seen traversing the epidermis 
quite outside these struetures, and were connected in the 
same manner with the epidermic cells. These arrangements 
unquestionably constitute a direct connection of nervous and 
epithelial structures. In most cases, but not in all, the 
nodule of attachment of the nerve-fibre coincided with the 
nucleolus of the cell. The mole’s nose is thus an exceedingly 
delicate organ of touch. It is calculated that there are on its 
surface 5000 papille, so that more than 100,000 nerve-fibres 
must terminate on it. 
2. ScuEenck (Schultze’s ‘ Archiv,’evol. vii, p. 192) discusses 
the formation of the amnion, seeking to fill up certain gaps 
in its history, especially as to its closure. He suggests that 
in addition to the division and multiplication of elements in 
the embryo rudimentary organs may also be formed and in- 
creased by elements which pass out of the vascular spaces, 
like emigrant leucocytes in the adult organism ; but was not 
able to observe any actual passage of elements through the 
vascular walls. 
3. Lrypic has investigated the organ of hearing in Gas- 
teropoda ; and confirms the discovery of Lacaze-Duthiers that 
the nerve to the auditory apparatus proceeds from the supra- 
