112 EXPERIMENT STATION RECOKD. 



Tlie author gives at consideiable leiij^th the details of his experi. 

 iiieiits, ill whicli he ibiiiid that many vegetable objects, alga? as well as 

 parts of higher plants, show under the intlueuce of dilute solutions of 

 coffein or antipyrin a great number of minute, transparent, colorless 

 globules that gradually unite, forming larger globules or drops. To 

 these minute globules the author has given the name proteosomes. They 

 are found in the vacuole as well as other i)arts of the cell. Spirogyro. 

 furnishes a good subject for examination, as the cells will live for some 

 time in the solutions above mentioned. If the objects in which the pro- 

 teosoines have been formed be taken from the solutions and placed in 

 pure water the globules will disappear as rapidly as the solution is dis- 

 placed in the cell by osmosis. If the cells are killed by long exposure 

 to the solution or by acids or salts of different kinds, the globules 

 change their properties, showing their close resemblance to the proto- 

 plasm of the cell. By a sudden loss of their absorbed water the pro- 

 teosoines coagulate and become insoluble, sliowing decisively their 

 chemical changes. Various reactions are given, showing that the pro- 

 teosomes respond to certain chemicals which have no effect on dead 

 protoplasm or other proteids, and even when killed the proteosomes 

 still are capable of reducing very dilute alkaline silver solutions, the 

 globules turning black. 



To demonstrate the fact that the proteosomes are active albumen, the 

 author cultivated Spirogyra in two solutions, one containing nitrogen, 

 the other without it. In the latter solution, after 2 or 3 weeks of 

 cultivation, no new albumen having formed, and that previously stored 

 having been used, no proteosomes were formed when subjected to the 

 coffein solution. On the contrary, the plants grown in the solution 

 containing nitrogen gave an abundant formation of them. 



The presence of active albumen stored up in the higher i)lants has 

 been demonstrated in numerous cases. It has been found in the leaves 

 of nearly all the insectivorous plants, the subepidermal cells of Cras- 

 sulaceWy the epidermal cells of Primula and Pelargonium^ the trichomes 

 of Begonia and other plants, the petals of Cyclamen^ Corn us, TuUpa, 

 and Ejyidendron, the anthers of Eugenia, etc.; the pistils of Crocus, 

 Rhododendron, Salix, and Euphorbia; the peduncles, petals, and young 

 seeds of Gentian a. Primula, Scrophularia, Impatiens, Pyrus malus, 

 Prunus eerasiis. Viburnum, iSorbus <iucuparia, and Thea ehinensis; the 

 flowers and young leaves of Bheum, Acer, Populus, Acacia, Cratmgus, 

 Mimosa, and the nectaria of Passi flora. In some plants it is found only 

 in certain stages of development, as in the petals of Malvw, unripe 

 berries of ^Symphoricarjms racemosus, the cotyledons of Rclianthus, and 

 in the larger cells of Vallisneria. It was not found in the leaves and 

 roots of Poa, shoots of Pisum and Vicia, or leaves, stems, and flowers 

 of Tussilago, Ranunculus, Veronica, and Convallaria. Its ])reseuce in 

 fungi is still problematical, and among alga*, Spirogyra, and sometimes 

 Vaucheria, are the most notable ones sliowing this kind of reserve 

 material. 



