Cog HILL, Ski>i of the Frog. 59 



possibly be interpreted as such. Furthermore, an occasional 

 chromatophore was found in the immediate vicinity of these 

 elements, which differed widely, both in structure and in reac- 

 tion to the stain, from the cells and fibers under consideration 

 (Fig. 14). Frequently a number of these cells are matted to- 

 gether in such a way as to form an irregularly shaped body, 

 from which numerous fibers of variable length ramify in all 

 directions. Often the fibers from different bundles are so closely 

 woven together that they appear to be continuous from one 

 cluster to the other, as indeed they may be. This type of cell, 

 however, is not confined to the stratum at the base of the co- 

 rium. It tends to wander peripherad. In such cases fibers from 

 one end of the cell have been traced for long distances till they 

 became lost in a complex of fibers, the destination of which is 

 in the stratum just described. (Fig. 13.) From the other end 

 of the cell, shorter fibers ramify among the surrounding tissue. 

 In some instances they seem to attach themselves to the peri- 

 phery of the glands of the ectal series. 



The function of the fibers arising from the lower stratum, 

 however, seems to be more intimately related to the glands of 

 ental series, for these fibers pass ectad in marvelous numbers 

 and embrace the entire surface of the glands. This condition 

 was demonstrated by the projection upon a median plane of 

 drawings made with the camera lucida from consecutive sections. 

 (Fig. 8, A-E). 



These fibers do not seem to be identical with those de- 

 scribed as innervating the tunic cells of the ental gland. They 

 differ from these in their distribution and relative positions. 

 They correspond, however, with the structures described by 

 President C. L. Herrick, in this Journal, Vol. VIII, p. 51 

 (Fig. 40, reproduced as Fig. 15, Plate V, of this article). 

 In this instance it was found that a net-work of non-med- 

 ullated fibers crossing at slightly different levels appeared 

 on glands in the toad, and that these fibers apparently 

 were connected with the ganglionic plexus at the base of the 

 corium, though the latter point was not certain. This relation, 

 however, is now satisfactorily demonstrated. It seems, there- 



