1883.] Protoplasm through the Walls of Vegetable Cells. 165 



on pulvini, and to set his investigtions on the firmest possible basis, 

 the author now commenced the study of endosperm cells, since in 

 them the cells were exceptionally large, and the pit membrane being 

 very thick, the presence of any threads running through its substance 

 would be likely to be clearly seen. Having confirmed Tangl's results 

 with Strychnos, Phoenix, and Areca, he examined in detail the seeds 

 of some fifty species of palms, and besides those of typical represen- 

 tatives of the following orders : — Leguminoseae, Rubiaceaa, Myrsinese, 

 Loganiceas, Hydrophyllaceae, Iridaceae, Amaryllidaceee, Dioscoriaceae, 

 Melanthaceae, Liliaceae, Smilacaa, and Phytelephasieae — in all of which 

 he found that the cells were placed in communication with one 

 another by means of delicate threads passing through the walls of the 

 •cells. In unpitted cells, e.g., Tamus and Dioscorea, the threads 

 traversed the whole thickness of the wall. In the greater number of 

 instances the cells were pitted, and the threads passed across the pit 

 membrane ; and in certain cases, e.g., Bentinckia, Kentia, Howea, 

 Lodoicea, and Asperula, communication was established both through 

 the thickened walls and through the pits. The endosperm cells displayed 

 in their structure every possible modification, both of thickness or 

 thinness of the pit membrane, of clearness or difficulty of observation, 

 and of degree of development of the middle lamella. The develop- 

 ment of the endosperm was not worked out in any case, but the cells 

 were shown to communicate with one an other at a very early period. 

 When sections of living endosperm tissue were treated with sulphuric 

 acid, and stained with Hoffmann's blue, the same results were obtained 

 as with pulvini, only here everything was on a much larger scale. 

 Thus both the methods and results received every confirmation. 



The author then treats of his investigations on the subject of 

 Plasmolysis, in which he had established that when the plasmolytic 

 condition is induced in a cell the contracted primordial utricle does 

 not lie free in the cell-cavity, but is connected on every side to tbe 

 cell-wall by means of numerous fine protoplasmic threads. His 

 experiments lead him to the conclusion that the above phenomena do 

 not give any definite assistance or confirmation to the study of 

 perforation of the cell- wall, for as often as not the threads bear no 

 relation to the pit, the only significance implied being that the 

 protoplasm and the cell-wall are intimately connected the one with 

 the other. 



Finally, the author remarks that, although he is aware of the 

 danger of rushing to conclusions, yet that when his results, which 

 were foreshadowed by Sachs and Hanstein when they demonstrated 

 the perforation of the sieve-plate, are taken in connexion with those 

 of Kussow, it appears extremely probable that the communication 

 between adjacent cells not only takes place in the parenchymatous 

 cells of pulvini, in the phloem parenchyma cells, in the cells of 



