510 L. BOLK 



of some constitutional disease. And as a rule rhachitis or 

 heredity syphilis are accused of being the primary causes of tlje 

 anatomical anomaly. 



It is clear that the literature on this subject principally refers 

 to the sagittal suture, because the deformity, which in some 

 cases results from the premature closure of the latter, has long 

 ■ since attracted the attention of anatomists. Concerning this 

 deformity, scaphocephaly as von Baer first called it, an extensive 

 literature exists, in which the question is widely discussed whether 

 scaphocephaly can be acquired alter birth, or is in each case 

 already present in the foetal skull. Although we shall not 

 enter into this question, it seems necessary to state the fact 

 that in all the skulls described in the preceding paragraphs, 

 the synostosis of the skull-bones had undoubtedly taken place 

 after birth and in the majority of the cases at the age between 

 the third and seventh year. 



Still I cannot agree with the opinion of the investigators, who 

 consider the premature obliteration as the result of rhachitical 

 or syphiUtical disposition of the individual and will give some 

 arguments against this theory. 



My first objection is based on the large number of skulls with 

 premature closure. If rhachitis or syphilis is the cause of it, 

 one must not shrink from the conclusion that one or the other 

 of these diseases has affected more than 15 per cent of the 

 individuals. 



I admit this argument to be purely theoretical and therefore 

 of a problematical value. Still there are other reasons why 

 the pathological nature of the premature obliteration should be 

 denied. In my collection of skulls there were, as need scarcely 

 be mentioned, a certain number with evident symptoms of 

 rhachitis: Hydrocephaly, flattened occipital region, defective 

 development of the enamel of the teeth, etc. A special exami- 

 nation has shown to me that the positive rhachitical skulls 

 were characterized in no manner by an increased tendency to 

 premature synostosis of the skull-bones. Amongst these rha- 

 chitical skulls there were naturally a certain number with pre- 

 mature closure of the sagittal or masto-occipital suture, but the 



