DR. BEALEj ON THE TISSUES. \) 



of the cells or nuclei, but merely upon the manner in Avhich 

 the calcareous matter is deposited in the formed material. 



No stellate corpuscle has been produced, but the stellate 

 appearance seems to result fi'om the circumstance that the 

 calcareous matter has been deposited in the matrix in such a 

 manner as to leave intervals of a form more or less stellate. 

 The reason of this will presently appear. The calcareous 

 matter is at first deposited so as to form a netvrork with nearly 

 cciual meshes. Each space contains an oval mass of living 

 germinal matter and is the earliest condition of a lacuna. 



The elementary parts concerned in the formation of lacunse 

 in the above specimen were represented in different stages of 

 growth under a power of 1700 diameters. 



The manner in which the earthy matter is deposited in the 

 matrix of the cartilage was represented in a diagram. It Avas 

 copied from a section of the temporal bone of a frog. Glo- 

 bules of earthy matter may be seen to form imperfect rings 

 around the cartilage cells. The calcareous matter is always 

 deposited in the matrix (formed material), at a point mid^vay 

 between adjacent " cells '^ that is in the oldest portion of the 

 formed material of the cartilage. The deposition gradually 

 proceeds from without inwards. The outer part of tlie ger- 

 minal matter of the cell gradually undergoes conversion into 

 matrix, which in its turn becomes impregnated Avith calcare- 

 ous matter until only a small space remains in which the 

 nucleus still exists. 



These stages were represented in drawings, and in many 

 specimens, especially from the frog, rounded globules of cal- 

 careous matter, which coalesce and imdergo great change in 

 form, can be demonstrated without difficulty in lacunae in an 

 advanced state of formation. Mr. Rainey has watched this 

 process, and seems to consider that molecular alterations in 

 the earthy particles are the essential changes to which the 

 formation of bone is due. 



Dr. Beale has examined the process of ossification as it 

 occurs in various animals with the aid of carmine, and has 

 always been able to demonstrate masses of germinal matter 

 in a position corresponding to the laeunal space. He believes 

 these masses of germinal matter to be as necessary to the 

 production of bone as they are to the foi'mation of every other 

 tissue, and feels certain they are constantly present, and that 

 through their agency alone, osseous, as well as all other tis- 

 sues, is formed. They are not directly concerned in the 

 deposition of the calcareous matter, but the matrix in which 

 this is deposited cannot be formed v/ithout them, and it is 

 probable that by their instrumentality alone the regular cir- 



