258 Barnes, So-callsd ,, Assimilation". 



synthetische Assimilation" to designate Avhat he had 

 previoulsy^) spoken of as assimilation. In reviewing Pfeffer 's 

 work Hansen^) calls attention to Pfeffers use of the word 

 assimilation. Hansen is impressed Avith the necessity of a 

 specific word (eindeutiges Wort) for the process of manufacture 

 of carbohydrates and proposes the term pho tosynthesis. 



In this proposition, however, he has long been anticipated. 

 Without any pretense at historical discussion, it may be liere 

 pointed out that W e i s n e r long since indicated the lack of a 

 suitable Avord. ßeferring to the process of carbohydrate-makin^, 

 he says : „Es scheint aber der im Texte gegebenen Begriffs- 

 umgrenzuDg an einem Worte zu fehlen iiir jenen wichtigen Process, 

 den man bisher als Assimilation bezeichnete"^). 



In a paper read before the Botanical Section of the American 

 Association for the Advancement of Science at its Madiso n 

 meeting in August 1893^), I proposed to supply this want by 

 the word pho tos j^ntax. This term I have since employed in 

 lecturing and writing and it has corae into use by a number of 

 students in this country. At the same time Professor Mac Mi 11 an 

 of the University of Minnesota expressed his preference for the 

 term photosynthesis, which in the same paper I indicated as an 

 available word, but rejected as etymologically less accurate. The 

 latter term has been taken up by Professor Mac Dougal 

 of the University of Minnesota and used by him, both in his 

 translation of eis 's Pflanzen physiologische Versuche 

 and also in his Experimental Plant Physiology. 



The propounding of the same term by Hansen is of value 

 only as a tardy recognition of the fact that the term assimilation can 

 no longer be correctly used. It is not important whether photo- 

 syntax or photosynthesis, or some other word, finally comes into 

 general use to describe the manufacture of carbohydrates by 

 green tissues under the action of light, It is high time, however, 

 that we drop as promptly as possible, the use of assimilation for 

 this or any similar process. The reasons for this I have set 

 forth at some length in the paper „On the food of green plants" 

 previously referred to, 



I may here take occasion to criticize Pfeffer 's defence 

 of the term assimilation. He says, „Wenn „Assimilation" ge- 

 legentlich speciell auf die Formation von Körperbausteinen, also 

 auf den organisatorischen Stoffwechsel eingeschränkt Avurde, so 

 dürfte es doch praktischer sein , dem üblichen Gebrauche zu 

 folgen und unter „Assimilation" auch diejenigen physiologischen 

 Processe zusammenzufassen, die im Organismus zur Herstellung 

 von plastischen Stoffen dienen. In solchem Sinne wird z. B. die 

 Production von Kohlenhydraten im Chlorophyllapparate als 



») Op. cit. p. -271. 



-) Botanische Zeitung. LVI. Abtli. II. 1898. p. 22. 



^) Elemente der Wissensch. Bot. I. p. 332. 



■•) Botanical Gazette. XVIII. 1893. p. 409. 



