HISTORY OF MITOCHONDRIAL RESEARCH 11 



searches that followed Altraann's postulation of the "Bi- 

 oblast Theory" have brought to light many interesting and 

 instructive activities and properties of these granules. 



The granules have been given various names, but recently 

 the term "mitochondria" suggested by Benda has come into 

 general usage, although the term ''chondriosome" is used 

 extensively. Mitochondria have various shapes, globular, 

 rod-Uke, filamentous and irregular. Various attempts have 

 been made to classify mitochondria according to their 

 shape, but as E. V. Cowdry ('18) has intimated in his ex- 

 tensive review of mitochondrial hterature, the shape of 

 mitochondria is of no particular significance. These classifi- 

 cations have not entered into common usage. With only a 

 few exceptions, mitochondria have been demonstrated in 

 all groups of plants and animals. It appears probable that 

 when a proper technique is used there will be no exceptions. 



It is not the purpose of this historical sketch to give a 

 detailed account of the literature on mitochondria. The 

 interested reader who desires to follow this in greater detail 

 is referred to Duesberg's review of the literature up to the 

 year 1912 (in German) and to Cowdry's review up to the 

 year 1918. The sketch given here is selective and mainly 

 intended to emphasize the salient features of mitochondria 

 that have been advanced in the literature, and which have a 

 direct bearing upon the principles of Symbionticism. 



A number of significant features and properties of mito- 

 chondria have been brought out in the hterature since the 

 pioneer researches of Altmann. In 1897 Benda studied the 

 formation of the spiral filament in the spermatozoa of the 

 mouse and found that mitochondria are transformed into 

 this structure. His observations have been confirmed by a 

 number of investigators. Meves ('12), Held ('12), Romeis 

 ('13), Faure-Fremiet ('13), Duesberg ('15), Levi and others 

 have observed that the mitochondria or their products enter 

 the egg with the sperm on fertihzation. On the basis of 



