10 Nebraska Agricultural Exp. Station Research Bi l. 10 
The differentiation of tissues and organs in the embryo 
of a mature kernel of corn is shown in Figures ’5-8. Figure 5 is 
a cross section thru the plumule surrounded by the scutellum. 
It may be seen how the young leaves are closely folded or curled 
up within the plumule. Figures 6, 7, and 8 are vertical sections 
1. The material from which these photographs were taken was secured 
from a yellow variety of ordinary dent corn, Hogue’s Yellow Dent. After soak- 
ing several kernels in water for about 12 hours, the scutellums were removed 
and dropped at once into Bowan’s Picric formol killing and fixing solution. 
They remained in this solution for 10 hours. Washing with 70 per cent alcohol 
was then begun and continued until the material appeared whitish and the 
alcohol was no longer tinted yellow. The material was then dehydrated in 
85, 95, and 100 per cent alcohol, after which it was cleared by bringing it up 
thru the xylol series. This consists of an alboholic dilution of xylol in the fol- 
lowing proportions: (1) 1 part xylol, 3 parts alcohol: (2) 2 parts xylol, 2 parts 
alcohol; (3) 3 parts xylol. 1 part alcohol; (4) pure xylol. Infiltration with paraffin 
was then begun by placing the material, together with a small block of paraffin, 
in a bottle of pure xylol. It remained in this bottle overnight and was then 
removed to the paraffin bath, where it remained for about 10 hours, and was 
then imbedded in paraffin. Sections were made of this material in the usual 
way and fastened on slides. The paraffin was removed from the sections with 
xylol, and the xylol removed with 95 per cent alcohol. This prepared them for 
the stain, methylene blue being used. They were stained for about 2 minutes 
and then dehydrated in 95 and 100 per cent alcohol, cleared with xylol, and 
mounted in balsam. The material was then in permanent form and could b© 
studied under the microscope at any time. 
Fig. 1 — Vertical section of kernel of dent corn. 
Fig. 2 — Cross section of kernel of dent corn. 
Fig. 3 — Growth after 35 hours favorable germination. 
Fig. 4 — Growth after 55 hours germination showing secondary roots. 
