SUGU EST IONS FOR I.All(>IiAT(HiY WoltK 



Leaf of Maize. 



Make sections across the veins and midrib, and treat as above. 

 Study tlie stnicturc of the bundles of the veins and tlio 

 luidril). iuid conijiare with those of the stem a.s already 

 observed. Compare the parenchyma of tlie section with 

 that of the Beuu leaf. 



Mount a bit of the epidermis, and com|)aro the forms of the 

 epidermal cells with tliose of corresponding cells in tiie 

 Bean. Study tlio stomata. Do they occur on one or both 

 surfaces ? 



Make draioimjs of the sections. 



Calyx and Corolla. 



If flowers of the Bean can be procured, sections of the calyx 

 and corolla may be made in the same way as the ordinary 

 loaf-sections. Determine if possible the cau.so of the 

 colour, if any, of the petals. Compare the texture of the 

 jietal with that of the foliage-leaf. Are there stomata? 

 vascular bundles '? 



Stamen. 



It is very difficult to make sections of the antlier of the Bean, 

 because of its minuteness, but the structure of the anther 

 of Marsh-Marigold maybe readily okserved, if .sections of 

 a young unopened flower are made. Note the two lar^fe 

 lobes, each containing two cavities or pollen-sacs separ- 

 ated by a partition. In mature anthers these partitions 

 are commonlj' broken down, so that each lobe then ap- 

 pears to be one-cellod. 



Is there a vascular bundle in the section ? 



Observe the pollen-grains, and if possible make out the origin 

 of the grains by free-cell formation. 



To observe the formation of pollen -tubes, make a moist 

 chamber as follows : Cut a rough piece of cardboard 

 the size of a slide, and make a hole in the centre some- 

 what smaller than a cover-glass. Soak the cardboard in 

 water and place it on the slide. Make a weak solution 

 of sugar (say 5 percent,), and put a drop of it on the 

 cover-glass. Place the pollen-grains in the drop and 

 invert the cover-glass over the hole in the cardboard. 

 Drying up can be prevented by occasionally wetting tlie 

 cardboard. Put the slide away in a dark place for about 

 18 hours. At the end of this time poIlen-tul»es will pro- 

 bably lie found in course of development, an.l may then 

 be studied with a higher power. 



Carpel. 



A carpel of the Bean may be cut acro.ss and the structure of 

 the wall compared with that of the foliage leaf. 



