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F. H. Herrich — Abnormal Hickory Nuts. 



Histology of the abnormal endocarp. 



The dense outer shell of the abnormal nut (fig. 10) resembles 

 closely in structure the normal endocarp just described, except 

 that the tissue is rather more compact and the cells are smaller. 

 (Compare figs. 9 and 10.) The cell-wall has a similar struc- 

 ture. There is the same kind of brown indurated matter fill- 

 ing the lumina of the cells, and the same kind of crystals are 

 occasionally seen. The structure of the dense wall of the inner 

 shell surrounding the nut is quite uniform, as represented in 

 fig. 11, from a transverse section. The cell-walls in this are 

 thick, laminated, and perforated by numerous canals, many of 

 which branch and communicate with the canals of adjoining 

 <3ells. (See cell «, fig. 11.) The brown indurated material 

 frequently fills both canals and lumen. 



The stem (figs. 1-a and 12) by which this inner nut was 

 attached to the tree, is an interesting structure. As shown in 

 the photograph, it has separated in one specimen from the nut, 

 and terminates in a shallow cup or expansion which suggests 

 the cupule of the acorn. 



It is light in color streaked with dark brown lines, which 

 assume the form of islands or irregular blotches at the ex- 

 panded end next the nut. A section, cut in the plane indi- 

 cated in fig. 12, has a singular appearance. It presents a finely 

 mottled pattern, and when examined microscopically is seen to 

 consist of colorless and colored sclerenchyma. The light 

 brown cells, which owe their color to the indurated cell-con- 

 tents, form a reticulated pattern. The tissue shows no direct 

 or unmistakable evidence of imbrication in the plane sectioned, 

 but I regret that the section did not pass through the axis of 

 the stem. 



