6o Journal of Comparative Neurology. 



fore, that there are two groups of nerves passing to the glands 

 of the ental series ; the one attaching by the typical endings to 

 the enveloping muscle cells, the other ramifying promiscuously 

 over the surface of the gland. 



It should be noted further that nerve bundles enter the 

 ganglionic stratum on its ental aspect, and that fibers, either 

 singly or in clusters, pass out of them and distribute themselves 

 among the fibers and cells of the plexus. The exact destina- 

 tion of these fibers cannot be determined, though it seems plau- 

 sible that a part of them at least terminate in the ganglion cells, 

 since the cells in the more peripheral parts of the skin send 

 long fibers into the plexus. Furthermore, in the skin of the 

 Axolotl it is known that such a relation exists between similar 

 cells and the nerve bundle. 



In submitting the above results, the writer gratefully ac- 

 knowledges the aid given him by President Herrick, under 

 whose supervision the investigations were made. 



methods. 



1. Chrom-acetic Acid. The skin was removed from the 

 top of the head of the frog on one side the median line and 

 fixed seven hours in the following solution : chrom-acetic acid 

 (Fol's formula), two parts ; water, one part; io% solution of 

 platinic chloride, ten drops to about two ounces of the pre- 

 paration. 



2. Flemming's Stronger Solution. The skin from the 

 top of the head of the same specimen as in No. i, on the other 

 side of the median line, was fixed seven hours in Flemming's 

 stronger solution. 



For tissues fixed in both these solutions the usual methods 

 of paraffin embedding were employed, and the sections were 

 cut serially. The stains used were as follows : 



(a). Delafield's alum haematoxylin and picrocarmine. On 

 a number of slides, the haematoxylin alone was applied, 



(b). Benda's sulphate of iron haematoxylin. With this 

 stain the best results were obtained by mordanting about one 



