CHEMICAL PHYSIOLOGY. 95 



substance in the thyroidean acini is not mucin ; it yields 

 no sugar on treatment with mineral acid, and it gives 

 evidence of phosphorus by Lilienfeld's new method ; pre- 

 sumably it is a nucleo-albumin (Gourlay, Proc. Physiol. Soc. 

 1893, viii.). 



The peptones have been the subject of three important 

 papers; one by Kiihne [Zeit. Biol., xxix. 1), who enters with 

 full details into the use of ammonium sulphate for the sepa- 

 ration of peptones from proteoses, and defends his position 

 against the attacks of Pekelharing, who does not consider 

 that any essential difference exists between peptone and 

 proteose. Kiihne also investigated the diffusibility of these 

 substances, and obtained the curious result that cleutero- 

 proteose is less diffusible than proto-proteose, a result inde- 

 pendently obtained also by Chittenden [Jour. Physiol., xiv. 

 483) in a comparative study of artificial and natural digestion. 

 The second paper treats of the chemical structure of peptones, 

 and is written by Schiitzenberger [Compt. Rend., cxv. 764), 

 a well-known worker in this field ; and the third of an 

 important physiological property of these substances by 

 Starling [Jour. Physiol., xiv. 131). When injected into the 

 blood, "peptone" produces loss of power of coagulation; 

 the peptone leaves the blood by the urine, via the lymph. 

 It can be detected by adding to blood or lymph an equal 

 volume of ten per cent, solution of trichloracetic acid ; this 

 precipitates the normal proteids of these fluids, and the 

 peptone is discoverable in the filtrate. 



In reference to albuminuria the most important paper 

 of the year is by D. Noel Paton [Proc. Roy. Soc. Edin., 

 xix. 102), who has observed the unique phenomenon of the 

 occurrence of a crystalline globulin in human urine. 



The most important papers on albuminoids are the fol- 

 lowing: On mucin in bone, by R. A. Young [Jour. Physiol., 

 xiii. 803), who finds that mucin is absent from compact 

 bone, the ground substance being entirely calcareous. On 

 synovial mucin, by E. Salkowski (Virchow's Archiv, cxxxi. 

 304); this substance appears to be neither true mucin nor 

 nucleo-albumin ; it contains no phosphorus but yields no 

 reducing substance. In an important paper by O. Ham- 



