90 THE CELL DOCTRINE, 



white blood-corpuscle into the red. In the spring of 

 the year many white corpuscles can be found in the 

 blood of the frog and newt, undergoing conversion 

 into formed material at their edges, where the usual 

 granular appeara'nce is being substituted by the 

 smooth and slightly colored. This goes on until all 

 except the nucleus is thus converted. In mammalia 

 this change goes on until the whole white corpuscle 

 is thus converted into the red. 



Secondary Formed Material. — There are certain 

 kinds of formed material to which this term is ap- 

 plied by Dr. Beale. These are the oil of the fat-cell 

 or vesicle and the starch-granule of the vegetable 

 cell. It results, as does all formed material, by a con- 

 version of the germinal matter into this special form. 

 The young fat-cell, as all young cells, is almost pure 

 germinal matter ; as it grows older, however, and is 

 exposed to oxidizing influences, the conversion of 

 germinal matter takes place, partly into the cell-wall 

 proper of the fat-vesicle, and partly into the second- 

 ary formed material or oil, until finally it becomes a 

 mere dot on the inner surface of the cell-wall, or dis- 

 appears altogether. 



The increase of cells, according to Beale, takes place 

 in several ways ; every cell coming from, a pre-existing 

 cell, but the germinal matter is always the portion 

 in which it originates. 



There is not generally a symmetrical division of 

 the nucleus into two, and these into four, as is so 

 often described, and as is often seen in the vegetable 

 cell, but there is rather a budding, and subsequent 

 dropping off of the portions of germinal matter 



