130 Profs. S. H. Vines and J. R. Green. [June 16. 



X. "The Reserve Proteid of the Asparagus Root." By S. H. 

 VINES, F.R.S., and J. R. GREEN, M.A., F.L.S. Received 

 June 10, 1892. 



The object of research was the determination of the nature of the 

 substance, presumably a profceid, from which is formed the asparagin 

 which is so abundantly present in the young shoots of the plant in 

 the spring. The researches were carried on during the springs of 

 1891 and 1892, and results have been obtained which are sufficiently 

 definite for publication. 



Microscopical Observations. When a transverse section of a fresh 

 root, taken from the plant while in a state of winter- rest, is mounted 

 in alcohol on a slide, and is at once examined witb the microscope, 

 some of the parenchjmatous cortical cells are seen to contain rela- 

 tively large masses of irregular shape. When water is run under the 

 cover-slip these masses at once dissolve. rom their general appear- 

 ance and their reaction with iodine these masses probably consist of 

 some form of proteid. 



Chemical Observations. 



a. Watery Extract. The watery extract was made by pounding 

 the fresh root in a mo'rtar with distilled water (generally 100 c.c. 

 water to 100 grams root), and straining off and filtering the liquid. 

 The resulting extract was faintly yellow, slightly opalescent, . and 

 feebly acid. On boiling it gave a dense precipitate, which gave a 

 good xanthoproteic reaction, thus indicating its proteid nature. The 

 liquid filtered off from the precipitate gave a faint xanthoproteic 

 reaction. In some experiments the extract was carefully neutralised 

 with ammonia to precipitate the phosphates, and then some common 

 salt (NaCl) was added to throw down a substance of unknown nature 

 but not a proteid, the presence of which was detected at an early 

 stage in the investigation; the neutral liquid then filtered off gave 

 only a turbidity on boiling; when the liquid was made slightly 

 alkaline the same result w'as given; but in. both cases when the 

 extract was made faintly acid a good precipitate was obtained on 

 boiling. The coagulation point was determined to be 71 73 C. 



The watery extract gave a good xanthoproteic reaction; a fairly good 

 reaction with Millon's reagent; no satisfactory reaction with acetic 

 acid and potassic ferrocyanide or with potassic hydrate and copper 

 sulphate. 



When alcohol in excess was added there was a dense precipitate 

 which at first was soluble again in water, but which became for the 

 most part insoluble if allowed to remain for some time in contact 



