6 MEMOIRS OF THE NEW YORK BOTANICAL GARDEN. 



farious phenomena of etiolation. It will be unnecessary in the 

 present connection to inquire into literature which does not bear 

 directly upon the results of etiolations and the influence of light upon 

 growth. Neither will attention be given to papers dealing with the 

 more strictly morphological aspects of the influence of light upon 

 form, as in dorsiventrality, etc. 



Payer, Gardner^^ and Draper^* investigated the activity of chloro- 

 phyl in various parts of the spectrum and also the general facts now 

 included under phototropism. Draper made cultures of peas in blue 

 light and in darkness. He notes that seedlings under the latter condi- 

 tion are pale yellow with no fresh leaves, and that a height of thirteen 

 times the normal was attained with the etiolated plant apparently into a 

 vigorous condition. Dutrochet^^ confirmed Pa^^er's results in the main. 



Meanwhile but little of the information gained by the late investi- 

 gations found its way into the text-books of botany. Carpenter"^ 

 gave the substance of DeCandolle's conclusions in 1848, and saw in 

 the non-development of woody fiber and of secretions the most im- 

 portant results of etiolation. The blanching of celer}-, sea kale and 

 other plants was recorded, and it may be assumed that this treatment 

 of salad plants was in more or less common practice at that time. He 

 cites the following diverting illustration of natural etiolations, which 

 is to be found in many European text-books of the period : "It fre- 

 quently happens in America that rain and clouds obscure the atmos- 

 phere for several days together ; and that during that time the buds 

 of entire forests expand themselves into leaves. These leaves assume 

 a pallid hue until the sun appears ; when within the short period of 

 six hours of a clear sky and a bright sunshine their color is changed 

 to a beautiful green." Another writer fortifies this statement with 

 the additional fancy " that a forest in which the sun has not shone 

 for twenty days, the leaves were expanded but were almost white. 

 One forenoon the sun began to shine in full brightness : the color of 

 the forest changed so fast that we could perceive its progress." 



An analysis of etiolated specimens of Pisiini sativum^ Hordeii7n 

 vulgare and Avena sativum by Vogel ""^ in 1856 led him to the gen- 



23 Gardner. London, Edinburgh and Dublin Pliilosophical Magazine. 1S44. 



2* Draper. Chemistry of plants. 1844. New York. 



^^Dutrochet. Rapport sur un mdmoire de M. Payer intitule: Memoire sur la tend- 

 ance des racines a fuir la lumiere. Ann. Sc. Nat. III. 2 : 96. 1S44. 



26 Carpenter, M. B. Vegetable Physiology, and Systematic Botany. P. 198. 1848. 



2' Vogel, A. Beitrage zur Kenntniss der Verhaltnisses zwischen Licht und Vegeta- 

 tion. Flora, 39 : 385. 1856. 



