F. Protamines--soluble in water and ammonia, not coagulated by heat, yielding large proportions of diamino-acids on hydrolysis. G. Albuminoids--insoluble in water, salt solutions, acids, or alkalies. 2. _Conjugated Proteins_ A. Chromoproteins--compounds of proteins with pigments. B. Glucoproteins--compounds of proteins with carbohydrates. C. Phosphoproteins--proteins of the cytoplasm, containing phosphoric acid. D. Nucleoproteins--proteins of the nucleus, containing nucleic acids. E. Lecithoproteins--compounds of proteins with phospholipins. F. Lipoproteins--compounds of proteins with fats, existence in nature doubtful, artificial forms easily prepared. 3. _Derived Proteins_ A. Primary protein derivatives. _a._ Proteans--first products of hydrolysis, insoluble in water. _b._ Metaproteins--result from further action of acids or alkalies, soluble in weak acids and alkalies, but insoluble in dilute salt solutions. _c._ Coagulated proteins--insoluble forms produced by the action of heat or alcohol. B. Secondary protein derivatives. _a._ Proteoses--products of hydrolysis, soluble in water, not coagulated by heat, precipitated by saturation of solution with ammonium sulfate. _b._ Peptones--products of further hydrolysis soluble in water, not coagulated by heat, not precipitated by ammonium sulfate, give biuret reaction. _c._ Peptides--individual amino-acids, or poly-peptides, may or may not give biuret reaction. The plant proteins which have been investigated, thus far, fall into these groups as follows: 1A. _Albumins_ Leucosin, found in the seeds of wheat, rye, and barley. Legumelin, " " pea, horse-bean, vetch, soy-bean, lentil, cowpea, adzuki-bean. Phaselin, " " kidney-bean. Ricin, " " castor-bean. 1B. _Globulins_ Legumin, found in the seeds of pea, horse-bean, lentil and vetch. Vignin, " " cowpea. Glycinin, " " soy-bean. Phaseolin, " " beans (_Phaseolus spp._) Conglutin, " " lupines. Vicilin, " " pea, horse-bean, lentil. Corylin, " " hazel nut. Amandin, " nuts of almond and peach. Juglansin, " seeds of walnut and butternut. Excelsin, " " Brazil nut. Edestin, " hemp seed. Avenalin, " oats. Maysin, " corn.