GRIFFITHS: A NOVEL SEED PLANTER 167 
accomplished. Sowings of seed collected in large quantities last 
spring have been made on several surfaces. Glass, tissue paper, 
blotting paper, clean sifted building sand, sand of a roadbed at 
Takoma Park, D. C., and some of the finer clayey soils have been 
used as seed beds. After being scattered the seed together with 
the substratum were moistened sufficiently to thoroughly distend 
the mucilaginous coatings. The behavior of the mucilage on the 
different surfaces when compared appears to me to indicate clearly 
its mechanical behavior in sinking the seed. 
Upon the glass surface not only was the structure of the muci- 
laginous covering easily observed, but it was demonstrated that 
upon drying it does not return to its original position around the 
seed. It flattens out on the support instead, serving in this way 
to attach the seed very firmly to the surface. When dried the 
seed will therefore be firmly fastened to the glass and have sur- 
rounding it two distinct zones. The inner zone will fave an irreg- 
ular radial striation and a dense heavy appearance indicating that 
the greater amount of the mucilage is concentrated there. It has 
the appearance of having been thrown into minute radial folds in 
drying. The outer zone is much wider, contains much less of the 
mucilaginous substance but has no well-marked structure. Its outer 
as well as its inner boundary is very irregular and there are in it 
very faint irregular and indistinct radial thickenings. When the 
seed is forcibly removed from the glass both zones may accompany 
it, but usually the outer one remains attached to the glass. 
When seed sown on blotting paper has dried, only a little of the 
inner zone of dried mucilage is apparent, the outer one being 
invisible on account of having sunken into the surface of the 
Paper. When the seed is forcibly removed only a part of the 
inner zone of dry mucilage accompanies it, the outer one invariably 
Femaining attached to the paper. Of course some of the paper 
usually accompanies the seed which is removed. 
On tissue paper the appearance does not differ materially from 
blotting paper, the outer zone here again being sunken into the 
Pats. There ia one decided difference, however. The paper has 
° tendency to wrinkle parallel to the long axis of the seed, leaving 
itin a trough of the folds with the elevations on either side. 
€ seed sown on clean building sand presented when dry a 
