INDEX. 



281 



Sulphur, its presence in keratin, 86 



,, a constituent of cystin, 151 

 Sulphuric acid, 52 

 Suprarenal bodies, pigment of, 271 

 Sweat, presence of urea in, 155 

 Synovial fluid, nucleo-albumins probably 



present in, 90 

 Syntonin, chemistry and preparation of, 



16 

 ,, definition of, 35, note 



Taurin, 142 



Tauro-carbamic acid, 143 

 Taurocholic acid, preparation of, 212 

 precipitation of proteids by 



means of, 213 

 Tea, traces of xanthin present in, 176 



,, hypoxanthin present in, 180 

 Teichmann's crystals (haemin), 236 

 Tendons, mucin of the, 78 

 Tetronerythrin, sources of, 269 

 Theme, its relations to xanthin, 175, 185 

 Theobroma cacao, its alkaloidal con- 

 stituent, 185 

 Theobromin, its relations to xanthin, 



174, 175, 185 



,, isomer of paraxanthin, 178 

 ,, an excretionary product of 



plants, 186 

 Theophyllin, its relations to xanthin, 



175, 179, 185 

 Tinned meats, possible development of 



ptomaines in, 206 



Torula ureas, enzyme developed by, 70 

 Touraco, presence of copper in plumage 



of, 231 

 Toxines, 206 

 Trimethylvinyl - ammonium hydroxide, 



137 

 Tropaeolins, classification of acid- and 



alkali-albumin by means of the, 17 

 Trypsin, its action on fibrin, 33 



its action on proteids, 35, 37 

 ,, preparations of, 61 

 Trypsinogen, the zymogen of trypsin, 63 

 Tunicin, 101 

 Turacin, 231 

 Tyrein, formation of, in clotting of casein, 



21 

 Tyrosin, a result of decomposition of 



proteids, 39 

 ,, a product of decomposition of 



mucin, 78 



,, constitution of, 190 

 ,, preparation of, 191 

 ,, Hoffmann's reaction for, 191 



Umbilical cord, mucin of the, 78 

 Urea, 155164 



average daily excretion of, 155 



preparation of, 156 



synthesis of, 156, 160 



nitrate of, 157 



oxalate of, 157 



Urea, detection of, in solutions, 159 

 ,, quantitative determination of, 159 

 , , its probable tissue-antecedents, 161 , 



162 

 its relations to uric acid, 170, 171, 



172 



Urea-ferment, its enzymic nature, 69, 70 

 Ureas, substituted, 164 

 Uric acid, 165170 

 ,, salts of, 166 

 ,, preparation of, 167 

 tests for, 167, 168 

 ,, chemical constitution of, 169 

 synthesis of, 169 

 ,, its relations to urea, 170, 171, 172 

 Urinary melanin, 258 

 Urine, fermentative changes in, 69 

 ,, pathological changes in, 70, 102, 

 108, 130, 204, note, 207, 258, 260 

 presence of kreatinin in, 144 

 urea the chief nitrogenous con- 

 stituent of, 155 



determination of nitrogen in, 160 

 sulpho-cyanates present in, 163 

 phenyl-sulphuric acid in, 195 

 pyrocatechin in, 197 

 pigments of, 252 257 

 Urobilin, its identity with hydrobiliru- 



bin, 247, 248, 249, 253 

 preparation of, 253 

 ,, spectra of, 254 

 normal and febrile, 255 

 ,, its relation to other pigment- 

 ary substances, 255 

 Urochrome, 256 

 Uroerythrin, 256 

 Urohsematin, 256 

 Urohaematoporphyrin, 256 



Valeric or valerianic acid, 118 



Van't Hoff-Le Bel hypothesis of iso- 



merisrn, 129 

 Vegetable alkaloids, their analogy with 



ptomaines, 205, 206 

 tissues, allantoin found in, 173 

 ,, xanthin found in, 176 

 ,, occurrence of hypoxanthin 



in, 180 



, , occurrence of guanin in , 184 

 occurrence of skatol in, 204 

 Visual purple, 262, 265 



action of light and reagents 



on, 266 

 Vitellin, chemistry and preparation of, 25 



Water, dependence of reactions on pre- 

 sence of, 52 

 ,, its service in the action of soluble 



ferments, 74 



Weidel's reaction for xanthin, 177 

 Weyl's reaction for kreatinin, 147 



Xanthin group, the, 174186 

 Xanthin, its relationship to uric acid, 175 



