Stopes and Fujii, The nutritive relations of the surrounding tissues etc. 17 



Certain it is, that in all the Gymnospenns we have so far 

 examined a thick pitted wall such as we have described is to be 

 found, and it is rernarkably uniform in its structure and appearance 

 in all the genera. 



General Conclusions. 



In the endosperm cells packed with stored food stuffs we find 

 large numbers of protein grains of considerable size in addition to 

 the starch (cf. fig. 5 and 8) and, as we have already pointed out 

 it would appear equally extraordinary to suggest that these grains 

 either of starch or protein, forced themselves from cell to cell as 

 such. The transit of carbohydrates as sugars has been known for 

 long, and the work of Schulze, Vines and others has taught us 

 that storage protein materials in seeds do not travel as such during 

 germination, but are first split up by the action of enzymes to 

 soluble simpler forms in which they pass from cell to cell and 

 which are later rebuilt to protein substances with the addition of 

 carbohydrates and mineral salts; and it is most probable that 

 practically the same thing holds good while the food is accumulating 

 in the young endosperm. Notwithstanding this we have found many 

 groups of very small pits in the cell walls of the usual endosperm 

 cells, the whole System of pits being just like that found in the 

 wall of the egg cell itself except that the groups are smaller, and 

 as the walls of the endosperm cells are thin, they are much less 

 conspicuous than they are in the egg wall. In theni too the pit 

 closing membrane will be traversed by groups of Plasmodesmen. 



Now therefore, when in the egg cell itself (where its very thick 

 wall renders the pits in it conspicuous) there are deposited starch 

 grains and protein grains, why should one be any more ready to 

 believe that the starch and protein stuffs entered the egg in this 

 solid form than one is in the case of the endosperm cells? 



The Statement of some workers, that there are large open 

 Communications through the pits between egg cell and jacket cells 

 is quite contrary to the facts we have observed, and the view that 

 protein granules pass from cell to cell as such, is against the 

 cnrrent acknowledged theories for the passage of food stuffs 

 between two neighbouring cells. Similarly the passage of whole 

 nuclei or large portions of thein through the membrane closing the 

 big pits, which is perforated only by Plasmodesmen pores far too fine 

 to admit even the individual chromosomes, (cf. fig. 1 and 2) nmst 

 be looked upon as an abnormal phenomenon. 



In this preliminary discussion of nutrition, we have confined 

 our attention to certain carbohydrates and protein substance in 

 general; but there are of course other important organic Compounds 

 such as amide, hexonbase, arginin etc. as well as inorganic salts 

 to be considered in the physiology of nutrition of the egg. They 

 will be treated in the second part of this research. 



As a result of our comparative study of the Gymnospenns 



Beihefte Bot. Centralbl. Bd. XX. Abt. I. Heft 1. 2 



