21 



liarity. It is higher up in the neck than a similar anomaly 

 in the Swan, Whooping Crane, and other birds. 



The President exhibited a specimen of Ornithichnite in 

 shale, split into two layers, the impression of a tetradactylous 

 foot. This, as well as other tracks in the same shale, has 

 the appearance of a double impression, as if two feet had 

 been placed in the same spot, and makes it somewhat 

 doubtful if they are not the impressions of a quadruped. 



The President also stated that he had received a slab of 

 sandstone, bearing an impression of the Otozoum. The 

 impression is that of four toes, all directed forwards, and 

 each track is twenty inches in length. 



Prof. Wyman stated that he had recently dissected a Tor- 

 pedo, (T. occidentalis Storer) and had directed his atten- 

 tion particularly to the termination of the nerves in the 

 laminae which compose the efficient part of the battery. 

 The results at which he had arrived agreed with those of 

 Wagner, who has made a special study of the minute 

 structure of the electric apparatus. 



The plates consist of an exceedingly thin membrane, which 

 appears to be nearly homogeneous, its surface showing only 

 traces of striations. On this membrane are distributed ultimate 

 nerve fibres and capillary vessels. When the primitive nerve 

 tube reaches the plate, it breaks up into numerous fibres, and 

 these in turn subdivide and reunite, so as to form a regular net- 

 work, with large meshes over the whole surface. Connected 

 with these last divisions of the nerve tubes, are to be seen pro- 

 longations, into which the white substance of Schwann either 

 does not enter, or if it does, extends only for a short distance, 

 so that the branch loses its double outline. Tiiis divides into 

 numerous branches, and frequently, at the point of bifurcation, 

 there is to be seen a large nucleated cell ; the ultimate branches 

 terminating, as described by Wagner, in an extremely delicate 

 filament, which seems to be lost on the surface of the plate. 



Prof. Wyman estimated the whole number of the plates at be- 



