I9I3] Alfred P. Lothrop 547 



Denis has failed to discover creatin and Creatinin in the urine of 

 elasmobranchs, but aside from this work, I know of no determina- 

 tions of the creatin-creatinin content, and the röle of these Com- 

 pounds, in the lower chordates. 



91. Influence of electricity upon metabolism. Matthew 

 Steel. (Laboratory of Physiological Chemistry, Long Island 

 Medical College.) Informal report. 



B. ABSTRACTS OF PAPERS FROM THE COLUMBIA BIOCHEMICAL 

 DEPARTMENT AND AFFILIATED LABORATORIES 



92. Studies of intracellular chemistry: A differential stain 

 for mucins and mucoids. Louis Berman and William J. Gies. 

 From a mixture of five parts of 0.25 per cent. sol. of safranin 

 (Grübler) and three parts of 0.25 per cent. sol. of methyl green 

 (Grübler), mucins and mucoids select the methyl green and are 

 colored green. In a 0.25 per cent, sol. of safranin alone, these gluco- 

 proteins are stained red. The following types of pure mucin and 

 mucoid preparations, which we prepared by the methods best 

 adapted for the highest purity of the products, stained green in the 

 safranin-methyl green sol. : mucoids from tendon, ligament, carti- 

 lage and bone; sodium salt of tendon mucoid; salivary mucin and 

 a sodium salt of salivary mucin ; ovo-mucoid. 



Samples of the following protein products, prepared by the best 

 methods and of the highest purity, selected safranin from such a 

 safranin-methyl green sol. and stained red: albumin {tgg), chron- 

 droalbumoid, collagen, deutero proteose, edestin, elastin, fibrin, 

 gelatin (from bone, muscle, ligament), hemoglobin, metaproteins 

 (acid albumin and alkali a^buminate), myosin, nucleoprotein (from 

 ligament and yeast), Ossein, osseoalbumoid, peptone. Dry blood 

 serum, tgg white and gluten also stained red in the safranin-methyl 

 green mixture. All these protein preparations stain green in a 0.25 

 per cent. sol. of methyl green alone. 



Glucothionic acids from the various glucoproteins named above 

 behave like mucins and mucoids in staining green in the safranin- 

 methyl green sol. The products obtained from glucothionic acid by 

 hydrolysis with boiling 5 per cent. hydrochloric acid sol. failed to 

 show the selective action. 



