50 TRANSACTIONS OP THE 



have been for the relief of disease of brain, injury of skull, epi- 

 lepsy, or convulsions. 



4. The operation was probably performed by scraping ; possibly 

 by a series of punctures. It seems likely that the first was employed 

 for children, and the latter for the harder skulls of adults. 



5. Posthumous trephining consisted in removing fragments of 

 the skull of a person upon whom surgical trephining had been per- 

 formed. 



6. Each' fragment was to exhibit a portion of the cicatrized edge 

 of the original operation ; and the purpose was, probably, to form 

 an amulet to protect from the same disease or injury, for relief of 

 which the operation had been performed. 



In reply to a question by Prof. Mason, Dr. Fletcher explained 

 that the Inca skull appeared to have been perforated by some 

 saw-like instrument, and that the operation was probably per- 

 formed only a few days before death. 



The President remarked that among Indians pathology consists 

 of a sort of mythical zoology ; that local diseases, such as sore eyes, 

 boils, etc., are attributed by them to the presence of worms, flies, 

 bees, etc., regarded as incorporated spirits. Their method of 

 curing such diseases consisted, therefore, in making openings for 

 the escape of these creatures. This was their conception of the 

 efficacy of blood-letting, which was extensively practiced. The 

 disease-organism escaped with the blood. Sealing was resorted to 

 for the same purpose, and a variety of punctures were made, differ- 

 ing in different cases. He suggested that all the cases of cranial 

 perforation might be accounted for as so many modes of letting out 

 the headache spirit or animal. 



Prof. Gore stated that he had observed in the Medical Museum 

 perforated skulls, containing within loose pieces of skull of larger 

 size than the orifice, and which, therefore, could not consist of the 

 piece cut out. 



