CoGHiLL, Skin of the Frog. 57 



and by the methylene blue method. The normal position of 

 these cells seems to be with their axis approximately perpen- 

 dicular to the surface of the skin, though in one instance a part 

 of them seemed to lie obliquely. This single exception to the 

 rule may, however, be interpreted as an artificial arrangement. 

 It can be affirmed with certainty of these cells that their function is 

 muscular. This position is sustained by the application of meth- 

 ylene blue which reveals a liberal nerve supply to them, and 

 the typical form of muscular nerve endings on their periphery. 

 (G. C. Huber and DeWitte, this Journal, Vol. VII, 3-4, Fig. 

 25.) In one instance (Fig. 9), sketched under the oil immersion 

 lense, the evidence by lower powers was sustained. Nodosities, 

 stained a deep blue, are seen to be connected by a fine fiber, ly- 

 ing in a position corresponding with that of the tunic cells. At 

 first there seemed to be a possibility that this appearance was due 

 to a precipitation between the cells, and that it sustained no 

 definite relation to them. But on closer examination it was dis- 

 covered that there were a number of these cells sufficiently im- 

 pregnated to show conclusively that the fibers with their vari- 

 cosities lie, not between the cells, but upon them. In another 

 instance, an individual cell teased from the gland showed the 

 same arrangement. Two plainly differentiated nerve fibers with 

 occasional nodules lie on the surface of the cell as if firmly at- 

 tached to it. Furthermore, on three successive glands of this 

 series non-medullated nerve fibers were seen to pass from the 

 ental portion of the corium to the glands, and to distribute 

 themselves there among the fibers and nodules on the cells, and 

 in some cases the fiber itself assumed the varicose form and be- 

 came very diminutive. These fibers going to the glands are 

 smaller than those going to the terminal cells, and their nuclei 

 are also smaller and shorter. This nerve connection is appar- 

 ently sustained by the other methods employed, excepting only 

 the Golgi, but the evidence from these methods is not such as 

 to be of itself convincing. 



As yet it has not been possible to trace these fibers to an 

 entrance into a bundle or as a single fiber for any distance be- 

 neath the corium, as was done in the case of the terminal fibers. 



