4. What is the significance of cranial tenderness? Where sensitiveness to cranial percussion is not due to a scalp lesion it is very suggestive of a tumor underlying this point. A gummatous lesion of the cranium itself, may occur without causing pain or increased sensitiveness. =CRANIAL NEUROSYPHILIS (focal syphilitic extraocular palsy) without mental symptoms.= =Case 28.= A chef, Paolo Marini, 28 years of age, reported that on awaking one morning, everything appeared double to him and that his right eyelid had begun to drop. In the following month Marini had begun to feel weak and to have difficulty in swallowing, as well as at times difficulty in breathing. The diplopia was found to develop when Marini looked to the right. Mentally, the patient was in all respects normal, and no other physical signs were found except the diplopia and ptosis above mentioned. The W. serum test was positive, but the tests of the spinal fluid were negative. =Diagnosis=: “CEREBRAL SYPHILIS.” 1. What is the anatomical cause of this condition? It is thought to be due in a number of cases to a small diffuse gummatous lesion at the _basis cerebri_. In the case of Marini this lesion appears to have been a little more extensive and to have interfered with the tenth and twelfth nerves also. 2. Why is the spinal fluid negative in such a case as that of Marini? Head and Fearnsides believe that intracerebral lues is characterized by a negative spinal fluid, under which circumstance one has always to consider the possibility of brain tumor or migraine in addition to the suspicion of syphilis. 3. What other causes besides syphilis should one consider for the sudden diplopia? Brain tumor, multiple sclerosis, cerebral arteriosclerosis, tuberculous meningitis, trauma and migrainous ophthalmoplegia, are not infrequently at the bottom of this condition. Cases also occur in which the etiology remains obscure, even at autopsy. Under antisyphilitic treatment, Marini slowly improved. =The SIX TESTS in TABETIC NEUROSYPHILIS (“tabes dorsalis”) may run milder than in paretic neurosyphilis (“general paresis”) and characteristically run somewhat like those of diffuse (meningovascular) neurosyphilis; in particular, the fluid Wassermann Reaction and the gold sol reaction are apt to run milder. The clinical course of tabes dorsalis is protracted and the prognosis as to life is good.=