In several papers on the sphenopalatine ganglion I have outlined what seemed to me the rôle1which it plays in nasal headaches and called attention to the topographic anatomy2of the district in which it lies, citing that the pterygomaxillary fossa is surrounded above, in front, behind and within by nasal structures and that in this respect it resembles an accesory nasal sinus; but that it is filled by the sphenopalatine ganglion, blood-vessels and connective tissue, instead of by air. I stated that inflammation in the surrounding nasal structures (accessory sinuses, sometimes the nasal membrane) produced by its extension to or the transmission of its toxins to the ganglion, a symptom-complex, partly neuralgic (painful); and partly motor, sensory and gustatory.3The neuralgic picture is pain in the root of nose and in and about the eye, in the upper jaw and teeth (sometimes lower jaw and teeth)