THE MITOCHONDRIAL CONSTITUENTS OF PROTOPLASM. 49 



avoid any confusion between the term " plastosomes " and the " plasmosomes " 

 of Arnold. It may also be remarked that there is a possibility of confusing 

 the term " plasto.some " with the "plasmasonie," or plasma-staining nucleolus 

 as contrasted with the karyosome, as well as the "plasomes," or elementary vital 

 units of Weisner, and the word "chondriome" with "chondroma," a cartilaginous 

 tumor. 



Still another series of names has been advocated, on the basis of. the plast-like 

 function of mitochondria ; for it is thought that the mitochondria are plast-f ormers 

 in plants and pigment-formers in animals. This view, so far as the plants are con- 

 cerned, has a good mass of evidence in support of it. We owe the term "chondrio- 

 plaste" to Champy (1913o, p. 157) and the term " chromochondries " to Prenant 

 (Asvadourova, 1913, p. 293). 



Reference may be made to the term "karyochondria," which Wildman (1913, 

 p. 428) introduced to describe certain mitochondria which he believed to arise from 

 the nucleus in spermatogenesis in Ascaris. Arndt (1914, p. 55) for the same 

 reason devised the term "Caryosomochondrien." 



Since it is difficult to bear in mind all these terms and their various shades of 

 meaning, we must make a more or less arbitrary selection of the one which appears 

 to be the least objectionable, for it would obviously be highly inadvisable to follow 

 the precedent and invent a new term. Priority is almost impossible to establish. 

 I have accordingly .selected the word "mitochondria" for the following reasons: 

 (1) Its introduction by Benda in 1899a (p. 397) marks the beginning of much of 

 the recent work on the subject; (2) ever since it has been, with but few exceptions, 

 in quite general use, especially in this country; (3) it is simple and does not commit 

 the user to any interpretation whatsoever. 



Duesberg (1917, p. 469) opposes this position, as stated in my paper (1916a 

 p. 424), as follows: 



"To this I take the liberty of making the following remarks: The term 'mito- 

 chondria,' in Cowdry's sense, is not in general use even in this country; if the nomenclature 

 must be based on morphology, one should, to be logical, reject 'mitochondria' as a general 

 term, for ' mitochondrium ' means granule and can not in consequence mean filament. 

 The analog>^ with the term 'cell' is not adequate, for, though this word is not appropriate, 

 it is, however, generally adopted; and it should not be forgotten that the invitation to use 

 a term in a different sense from its original meaning comes in this case precisely from 

 those who want to use 'mitochondria' as a general expression." 



In answer I venture to point out : 



(1) In 47 out of the 55 or more papers published in this country during the last five 

 years (1912-1917) the term "mitochondria" has been used in the general sense, that is to 

 say, in 85 per cent. 



(2) The word "mitochondria" was introduced by Benda (1898, p. 397) and is derived 

 from the Greek filros, a thread, and x^«'5pos, a grain. In order to interpret it as granules 

 one must ignore the "mito." That mitochondria are not simply granules (as Duesberg 

 asserts) is also made perfectly clear by Benda himself (1899a, p. 382), who refers to them 

 continually as " Fade nkornern." The term "mitochondrium" is the Latin singular of the 

 Greek compound word. The correct Greek singular is mitochondrion.^ 



'I am indebted for this information to Professor Miller, of the Greek department, Johns Hopkins University. 



