cook: ivory palms in Panama 141 



be closely adherent to the endocarp or shell of the nut, or free and 

 readily separable from the nut. One species has the sheath much 

 larger than the nut as though separated in the fresh state by a 

 layer of pulp. 



Style. In most of the species the style disappears in advance of 

 the maturity of the fruit, but one of the new species from Panama 

 has a persistent woody style. 



Columella. Most of the species have a short column or bundle 

 of compacted fibers suspended from the center of the cortex of 

 the fruit in the position of a placenta. The species with the per- 

 sistent style also has a more specialized, persistent columella 

 extending down between the nuts nearly to the position of the 

 -. hilum. 



Hilum. The hilum is very prominent in some species and 

 nearly flat in others. The shape differs from long oval or ellip- 

 tical to nearly round. The fibrovascular pits are irregular and 

 scattered over the surface of the hilum in some species while in 

 others the pits are nearly round and confined to a relatively small 

 area in the middle of the hilum. 



Adhilum. This name is applied to a peculiar specialization of 

 the shell of the nut to form a distinct process or spine at the upper 

 angle of the margin of the aperture, close to the hilum. In some 

 species the adhilum is a small rounded -prominence or angular 

 tooth, but in^other cases it is developed into a slender acicular 

 spine. The adhilum is formed of the same hard material as the 

 shell of the nut, but is so brittle that it is usually broken off in 

 removing the mesocarp, which may explain why it has not been 

 noticed before. 



Seed coats. The shell of the nut has a lining of fine fibrous 

 material through which the branches of the raphe are distributed. 

 In some species this lining is free from the true seed coat and in 

 others completely united with it. In the former case the branches 

 of the raphe are not exposed, but appear as raised veins on the 

 lining of the shell. In the latter case the branches of the raphe 

 are exposed on the kernel as it comes from the shell, because the 

 fibrous lining is torn apart into two irregularly separated layers, 

 one adherent to the inner surface of the shell, the other to the 

 true seed coat. 



