NERVUS FACIALIS OF ALBINO MOUSE 83 



pathetic ganglia there is an abundance of very fine fibers, which, 

 together with the thickness of the sections, is responsible for ob- 

 scuring the individual cells. 



The heads were cut from the body in the lower cervical region, 

 and in most instances were cut in halves following the second 

 treatment with ammoniated alcohol. These smaller pieces were 

 much more easily handled and gave more satisfactory sections 

 than the heads which were carried through whole. Sections 

 were cut 15 m in thickness and mounted in series. Six sagittal 

 series, six transverse series, and two horizontal series of half 

 heads, and one horizontal series of a whole head were used in 

 this work. 



The method used in following the nervus facialis varied 

 with the particular part under consideration. Perhaps the most 

 useful consisted of making outline drawings of each section or of 

 sections at regular intervals and tracing the different parts of 

 the nerve from drawing to drawing. Another valuable method 

 was a graphic method recently devised by Prof. A. G. Pohlman 

 and explained to me during a visit to his laboratory. This 

 method was less time consuming than profile reconstructing and 

 gave results easy of interpretation. By projecting sagittal sec- 

 tions onto a median plane, flat reconstructions of parts of the 

 nerve were made. In a few instances, to bring out important 

 details, blotting-paper models were made. 



In order to determine as far as possible the distribution of 

 certain branches of the facial nerve, it was necessary to undertake 

 and record a study of the nerve supply to parts of the head, 

 namely, the sphenopalatine ganglion and the nerves connected 

 with it, the nerve supply of the auricle, the nerve supply of the 

 palate, the nerves to the submaxillary and sublingual glands, and 

 the nerves in the tongue. 



I am greatly indebted to Prof. A. G. Pohlman for permission 

 to use his graphic method in advance of its publication, to Prof. 

 Burton D. Myers for library facilities extended to me on numer- 

 ous occasions, and to both of them for helpful suggestions during 

 the course of this work. 



