98 D. A. RHINEHART 



Medially the sphenopalatine ganglion is separated by the 

 bone from the nasal cavity. Laterally it is related to the max- 

 illary nerve throughout its entire extent, the sphenopalatine 

 nerves extending ventrally along its lateral side at about its 

 middle. 



The sphenopalatine ganglion of mammals is described as receiv- 

 ing the sphenopalatine nerves from the maxillary nerve and as 

 giving off branches which are distributed to the mucous mem- 

 brane of the nose, mouth and pharynx, and branches to the orbit. 

 All of the nerves which are usually mentioned in connection with 

 the ganglion, with the exception of the pharyngeal branch, are 

 represented in the mouse by similar nerves. 



a. Nervi palatinus posterior et medius. The posterior and 

 middle palatine nerves arise from the lateral side of the maxillary 

 nerve widely separated and distinct from both the sphenopalatine 

 ganglion and the sphenopalatine nerves. They will be described, 

 therefore, before the sphenopalatine nerves. 



The posterior palatine nerve is represented by one or two small 

 nerves coming from the lateral side of the maxillary nerve at the 

 level of the middle of the pesterior part .of the sphenopalatine 

 ganglion (fig. 4, N.Pal.P.). It is separated by the maxillary 

 nerve from the sphenopalatine ganglion, and arises from a part 

 of the maxillary nerve which gives off branches for the supply of 

 the teeth and gums of the upper jaw. 



The posterior palatine nerve receives two small bundles of fine 

 fibers from the ventral border of the sphenopalatine ganglion 

 (fig. 4, d,e). These pass laterally, ventral to the maxillary nerve, 

 and join the posterior palatine immediately before it enters the 

 canal in the bone through which it passes to the palate. They 

 are so small that in some series it is difficult to follow them even 

 by using the high power of the microscope. Unsuccessful at- 

 tempts were made to count the fibers they contain. I believe it 

 safe to conclude, however, that they do not exceed thirty-five or 

 forty in number. 



The middle palatine nerve is represented by a single smaller 

 branch which takes origin from the ventral side of the maxillary 

 nerve. This nerve passes inferiorly where it, too, enters a canal 



