1886.] 



Proteid Substances in Latex. 



39 



The body most nearly resembling this which has hitherto been 

 described is that which is stated by Martin* to be produced by the 

 action of papain on the proteids present in papain juice. It differs 

 from the one now described in that it gives the biuret reaction, and 

 is precipitated by acetic acid and potassic ferrocyanide. He says 

 nothing as to its power of dialysis. 



2. Hemialbumose (Lactuca) — 



a. Soluble in distilled water. 



b. Not coagulated on boiling. 



c. Precipitated by nitric acid and by acetic acid and potassic 



ferrocyanide. 



This resembles very closely Vines's hemialbumose, and the body 

 which Martin* has called a-phytalbumose. It differs in not giving 

 the biuret reaction. 



3. Albumose (Mimusops') — 



it- - 



a. Soluble in distilled water. 



b. Not coagulated by boiling in neutral solution. 



c. Precipitated slowly by nitric acid at a temperature approach- 



ing 70° C. 



d. Not precipitated by acetic acid and potassic ferrocyanide. 



4. Albumin (Brosimum) — 



a. Soluble in distilled water. 



b. Coagulated at 68° C. 



c. Not precipitated by acetic acid and potassic ferrocyanide. 



5. Globulin (Manihot) — 



a. Precipitated by dialysis of its solution. 



b. Coagulated on heating to 74 — 76° C. 



c. Precipitated on saturation of neutral or acid solution with 



solid MgS0 4 . 



d. Precipitated on large dilution. 



e. Precipitated by a stream of C0 3 through dilute solution. 



Both the albumin and the globulin seem to be the same bodies as 

 described by Martin as occurring in Papaw juice. The probable 

 identity of the former with Boussingault's vegetable fibrin has already 

 been alluded to. 



* Loc. cit. 



