Vol. 27 



No. 1 



BULLETIN 



OF THE 



TORREY BOTANICAL CLUB 



JANUARY 1900 



Turgidity in Mycelia 



By Carlton C. Curtis 



Although the question of the mechanics of growth has been 

 canvassed since the time of Nageli by so many writers as Schmitz, 

 Krabbe, Wortmann, Strasburger, Eschenhagen, Askenacy, Zacha- 

 rias, Noll, Schwandener, Strange, Reinhardt, Hegler, Pfeffer, 

 True, and Copeland, we must still agree with Krabbe, that an ac- 

 ceptable theory of growth does not exist. Especially are we in- 

 debted to the researches of Pfeffer as set forth in the u Druck und 

 Arbeitsleistung durch wachsende Pflanzen ri and the second part 

 of " Studien zur Energetik der Pflanzen M for an elucidation of the 

 various phenomena associated with growth. Especial attention is 

 called by Pfeffer to the fact that the mechanics of growth may 

 not only vary in different cases, but that all growth is dependent 

 upon the cooperation of many factors. Consequently the retard- 

 ing or quickening of the rate of growth may not be ascribed to 

 any one agency. So in regard to turgidity its action may be 

 more than counter-balanced by other forces, and we find no ''fixed 

 relation between the turgor force, stretching of membrane, and 



* 



rate of growth." The present work was undertaken to determine 

 just w r hat relation turgidity sustains to growth when all other 

 conditions, so far as possible, are kept constant and only known 

 variants are introduced. The hyphae of fungi were used for these 

 observations. They were grown in nutrient solutions of varying de- 

 grees of concentration and transferred to solutions of higher or 

 lower concentration. In this way wide variation of turgidity was 

 created, and as the moment of the renewal of growth in the hyphae 



[Issued 24 January.] ( \ } 



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