78 Physico-Chemical Properties of Vegetahle Saps [March, 



sues is greater with respect to electrolytes than to non-electrolytes. 

 Again, the apparently higher mean molecular weight of the solutes 

 from the abnormal tissues evidences in favor of the presence of 

 greater quantities of non-dissociated substances. 



In conclusion we should like to State that this paper is purposely 

 limited strictly to the presentation of facts. That the Statements 

 concerning matters of fact are sound is, we believe, established by 

 the high degree of consistency in the results of numerous physico- 

 chemical determinations based on very large masses of biological 

 material. 



We feel that in the present State of our knowledge an attempt 

 to discuss the physiological significance of these results is prema- 

 ture. For the present, the imperative need of physiology is sound 

 quantitative measurements of essential variables, and härm rather 

 than good is done by premature theoretical discussions. 



LITERATURE CITED 



DixoN, H. H. and W. R. G. Atkins (1913). Methods of extracting 

 sap from plant Organs. Sei. Proc. Roy. Dublin. Soc, n. s. 

 13, 422-433. Also, Notes Bot. Soc. Trinity Coli., Dublin, 2, 



154-165. 



GoRTNER, Ross AiKEN and J. Arthur Harris (1913). On a possible 

 relationship between the structural peculiarities of normal 

 and teratological fruits of Passiflora graeilis and some 

 physico-chemical properties of their expressed Juices. Bull. 

 Torrey Bot. Club., 40, 27-34. 

 (1914). Notes on the technique of the determination of the 

 depression of the freezing point of vegetable saps. Plant 

 World, 17, 49-53- 



Harris, J. Arthur (1906). Prolification of the fruit in Capsicum 

 and Passiflora. Ann. Rep. Mo. Bot. Card., 17, 133-145. 



Harris, J. Arthur and Ross Aiken Gortner (1914). On the influ- 

 enae of the Order of development of the fruits of Passiflora 

 graeilis upon the frequency of teratological variations. Plant 

 World, 17, 199-203. 

 (1914). Notes on the calculation of the osmotic pressure of 

 expressed vegetable saps from the depression of the freezing 

 point, with a table for the values of P for A = 0.001° to 

 A = 2.999°. Amer. Jour. Bot., i, 75-78. 



