128 SCIENCE PROGRESS 



germinate and show a vigorous development in the complete 

 absence of oxygen when an adequate supply of sugar is 

 present. O. Nobokich l showed that in Indian corn {Zea Mays) 

 normal karyokinesis may continue during forty-three hours in 

 the absence of oxygen. 



Palladin sums up his researches thus : 



" As to the capacity of plants in general to endure the 

 withdrawal of oxygen (anaerobiosis) one may say — disregarding 

 single instances of certain sharply defined cases — that the 

 lower plants support anaerobiosis better than the higher and 

 the embryonal or young stages better than the full grown." 2 



From this wide series of researches on the most diverse 

 organisms of both the animal and vegetable kingdoms, it is 

 evident that we have here, first of all, one of the most admirable 

 and best sustained proofs of the fundamental validity of the 

 recapitulation. theory or biogenetic law, free from the personal 

 bias of investigators ; and secondly a broad curve of continuity, 

 in "individual development, parallel to the same curve of con- 

 tinuity which obtains in racial development. Alike in the 

 single organism, as in differing types, the need of oxygen is 

 the result of and increases proportionally with increasing com- 

 plexity of organisation. 



But apparently the simplest cell which we know is itself 

 a highly complex symbiosis, colony or society of independent 

 living units. 3 In no other way can we account for the char- 

 acteristics and life activities of the granules or plastids which 

 are seen growing and dividing in the living cell and whose 

 division is apparently precedent to the division of the cell 

 itself. 



Let us now prolong this curve of decreasing oxygen need 

 with decreasing complexity and it is apparent that we soon 

 reach a point where this need approaches zero. Have we any 

 right to assume that this curve is an asymtote ? Clearly the 



1 Cited after Lesser, I.e. 



3 Zeit.f. d. Ausb. d. Entw. lehre, 206, 3, 1809 (with full reference to previous 

 papers). 



3 For literature cf. M. Heidenhain, Plasma u. Zelle, IV. Abs. {die Granulalehre\ 

 p. 327 ff.Qena, 1907) ; R. Altmann, D. Granidatheorie, 2te auf. (Braunschweig, 

 1894) ; G. Schlater, Zelle, Bioblast u. leb. Substanz (St. Petersburg, 1903) ; Wilson, 

 The Cell in Development and Inheritance, p. 22 (New York, 2nd ed. 1900); 

 O. Hertwig, Allg. Biol. p. 26, 3te auf. (Jena, 1909). 



