154 PHYSIC 



tures, as well as the muscular coatings of the blood vessels 

 and other structures endowed with muscular elements. 

 The explanation of this would seem to be that the involved 

 muscular structures have been deprived of the nutritive 

 plasma necessary for the maintenance of their sarcous 

 tissue, the supply of which is due to their related nerva- 

 tures, and that degeneration and removal of their existing 

 sarcous elements takes place, resulting in the collapse and 

 agglutination of the muscle fibre sheaths and the inter- 

 stitial muscular substance. 



Accompanying or following this process may take place 

 the formation of a degenerate species of organisation, 

 consisting, apparently, of the union of the formative ele- 

 ments on which the evolution of cartilaginous, osseous, or 

 calcareous growths in physiological developments and 

 pathological production are alike due. 



As the notochord produced the vertebral column by 

 intermixture of tissue plasma and earthy salts, as the 

 skeleton was produced by leakage of cerebro-spinal fluid 

 into the membranous or cartilaginous matrix at the skeletal 

 points or centres of ossification, so have the leaking neuro- 

 musculatures concerned initiated and continued the patho- 

 logical processes of the conversion of sclerosis into ossific 

 and, by continuation, into calcareous structures by an 

 unbroken series of malformative changes. 



This mal-formative procedure may be the outcome of 

 specific predisposing and exciting causes constitutionally 

 evolving themselves, or it may be due to traumatic and 

 other influences rapidly or more slowly initiating and 

 determining the phenomena in the seat of injured neuro- 

 musculo-skeletal structures and associated non-systemic 

 nervine tissue elements. 



