NERVUS TERMINALIS: MAMMALS 35 



blance to networks found by Ranson and Billingsley ('18) in 

 the cervical ganglion of the dog. 



An attempt was made to analyze the various strands of the 

 plexus, in order to determine, if possible, the types of component 

 nerve fibers. As previously stated, both myelinated and un- 

 myelinated fibers are present. Of the latter type, both varie- 

 ties, namely, fibers of Remak and naked filaments, are abundant. 

 While for short stretches some of the strands appear to be com- 

 posed exclusively of one type or the other (figs. 5, 6, 8, 19), the 

 rule is mixed strands. The fibers of Remak predominate as to 

 number when the entire plexus is considered. They are particu- 

 larly numerous near the main ganglion, and appear to include 

 the majority of fibers which enter this ganglion. 



In figure 20 are shown two converging strands consisting prin- 

 cipally of Remak's fibers, which approach this ganglionic mass. 

 The bundle resulting from their union was one of the most com- 

 pact of the entire plexus. Naked filaments of several sizes are 

 also included in it. One of the most slender of these (fi) is seen 

 to approach the nerve cell represented in the figure and to follow 

 what appeared to be the axone of the cell, to end on the perikar- 

 yon in a simple pericellular termination. A similar strand, but 

 with fewer naked fibers, is shown in figure 21, which was drawn 

 from near the ventral border of the posterior part of the olfac- 

 tory bulb. This bundle of fibers runs parallel with one of the 

 arteries of this region. An offshoot (ram.) consisting of four or 

 five threads leaves the main stran(i and passes to the wall of a 

 branch of the artery. 



Two fibers which show no neurilemma sheath leave the strand 

 to pass to the wall of the main artery. These strands so closely 

 resemble others, the terininations of which are described below, 

 that it seems certain that they represent fibers which ramify 

 to form the type of nerve-endings shown in figures 24 to 29. 

 Whether or not the fibers of Remak terminate in the sensory end- 

 ings represented in figures 28 and 29 could not be determined 

 with certainty. It seems unlikely, in view of the fact that the 

 fibers leading to the sensory terminations show myelin sheaths 

 near their endings. The naked filaments show considerable 



