16 SEEDS 
distilled water, thru the glass tubes once a week or 
oftener if necessary, and study the development of the 
plants until the close of the course. 
Results; conclusions? 
Literature. 
Spalding: Introduction to Botany...5.. 00... 5.20000 cee 23-28 
Leavitt: Outlines of Botany. .360..00.0506 i eo eee 15-23 
Coulter: .Text-book:of Botany ?:. os... 63009 Sa eee 84-97 
Stevens: Introduction to Botany..........% >. sc6e.. a. ase 16-27 
Histology of Seeds. 
Ask the instructor for a pea that has been in glycer- 
in for some time. With a sharp razor cut thin cross 
sections of one of the cotyledons, put them on aslide, 
add a few drops of 50 per cent glycerin and cover them 
with a cover-glass. Study the sections carefully with the 
low power and note that they contain numerous holes, 
many of which are filled with granules. These holes are 
known as cell-cavities, and the substance between the 
cavities composes what is known as cell-walls. A cell 
cavity with its contents, surrounded by a cell wall, 
constitutes a cell. All cells, however, do not have a wall. 
Find a thin place in one of your sections, move it to the 
center of the field, carefully turn on the high power, and . 
study the cells. You will find granules of various sizes 
in them. The large ones are starch granules and the very 
small ones proteid granules. Turn on the low power, 
remove the slide from the stage, add a drop of dilute 
iodin to one edge of the cover glass and apply a piece 
of blotting paper to the opposite edge until the iodin 
has been drawn under far enough to reach some of the 
sections but not all. Now study the sections both under 
