FOREWORD 



One cannot read this book by Professor Guilliermond with- 

 out being profoundly impressed with the thoroughness with which 

 it has been written. No one has yet presented, nor is any one for 

 a long time likely to present, so complete and authoritative an 

 account of the mitochondria story. Most of us have been rather 

 bewildered by the prolific, detailed, and contradictory literature on 

 mitochondria, chondriosomes, chondrioconts, chloroplasts, amylo- 

 plasts, plastids, etc. It is, therefore, a satisfaction to have it all 

 assembled in a relatively condensed form. 



I remember the day, it was a meeting of the Royal Microscopical 

 Society in London in 1921, when a number of cytologists admitted 

 that they were at last convinced that mitochondria are not arti- 

 facts. Guilliermond handles the subject of artifacts very con- 

 vincingly. He is forced to because much of his work has been on 

 fixed material and much of it has been subjected to the usual cry 

 of "artifact". 



Guilliermond uses one bit of evidence in support of the reality 

 of certain cell structures which I should like to apply to another 

 part of the cell, the existence of which has also been much ques- 

 tioned, namely, the spindle fibers. Proof of the reality of vesicles 

 is to be had, says Guilliermond, in the fact that they always 

 appear at the same stage of development of the cell whatever the 

 fixative employed. This is likewise true of spindle fibers. 



Shimamura has recently offered evidence of the existence of 

 spindle fibers by showing that if a cell in midmitosis is centrifuged 

 and then fixed, the spindle with fibers is found to be centrifugally 

 distorted. Centrifuging cannot distort an artifact before it has 

 been formed by fixation. 



Though supporting the reality of mitochondria. Professor 

 Guilliermond in no way enthuses unduly over their possible sig- 

 nificance in the life of the cell, as have some other workers. He 

 regards as untenable the theory that chondriosomes are symbiotic 

 organisms. He also discards the idea that chondriosomes are the 

 means by which every synthesis in the cell takes place. In reject- 

 ing the theory that chondriosomes are distinct organisms, a concept 

 based on their superficial resemblance to bacteria and the fact that 

 both are stained by the same dyes, Guilliermond shows a breadth 

 of mind characteristic only of the true scholar. He says, that 

 though the theory is untrue, it gave rise to much good research. 

 He concludes the section on the function of mitochondria by the 



