lA r . ün the continuity of the protoplasm through tlie walls of vegelable cells. 71 
Smilaceae 
Ruscus aculeatus. 
Phytelephasieae 
Phytelephas macrocarpa. 
The endosperm cells of seeds which are distinguished by their horny 
or cartilaginous character, are usually remarkable for the great thickness of 
their walls and offen for their large size. 
In by far the greater number of instances such cells are freely pitted 
although somo rare exceptions to this typical structure are met with, as in 
the cells of Turnus communis, and Strychnos nux-vomica, the walls of which 
are uniformly thickened, and displav no pitting whatsoever. Endosperm 
cells displav every possible modilication both of their size, of the thickness 
or thinness of the pit-closing-membranes and degree of development of 
their middle lamella. Thus while they are large in such endosperms, as 
Lodoicea, Caryotu and Manicaria, they are equally small in Geonoma, Cha- 
maedorea, and Nemophila. The pit-membranes though extremely thiek as 
in Hoioea, Latania and Helerospathe, are usually thinner as in Manicaria,- 
Synechanthus or Syagrus, while in ßomarea, Ruscus and Aucuba, their 
degree of development differs but little from that which occurs in ordinarv 
vegetable tissue. The middle-lamella is often very inconspicuous as in 
Turnus, Strychnos, llowea, Bentinckia or Latania, but in other cases, e.g. 
Stevensonia, Calamus and Ptychosperma it is unusually pronounced. 
With regard to their cell-contents one notices that as the seed ripens, 
great changes take place which linally end in the death of the cell. The 
nucleus usually becomes diffuse in outhrie and at length refuses to stain 
with Haematoxylin, and the protoplasm begins to shovv great alteration, 
and to diminish in quantity.') 
Alemone-grains may be present as in Tamus and Corypha, and cry- 
stalloids as in Martinezia and Diplothemium , but more usually the prolo- 
plasm becomes scanty, and in its stead large granules make their appearance 
and very generally drops of oil, as in Cocos, Strychnos, Kentia, and Brahea . 1 2 ) 
Finally the embryo represents the only living part of the seed, and 
upon germination, it simply preys upon, and gradually absorbs the dead 
endosperm cells, and whatever nutritive matter they may contain. 
When sections of such endosperms, after having beeil swollen with 
Chlor. Zinc. Jod., and stained with Jodine — in those cases where owing to 
the small percentage of water present, the usual cellulose blue is not pro- 
duced — or with Picrie Hoffmank’s blue, are carefully examined, it can be 
1) In some seeds liowever it may be doubted as to whether the cells are dead e. g. 
Tamus. The fact was only noted in a few typical instances. 
2) In the case of oily seeds the oil must be extracted with etber before treatment 
with Sulpliuric acid or Chlor-Zirik-Jod., otherwise it will stnear oVer the sections. 
