36 ART. 4. A. YASUDA : ON THE 



that of tlie stem. It is mostly roundish, and in some cases it is 

 more or less triangular or square, according to the number of 

 fibro-vasculer bundles present. 



Perklet'rn. Although the formation of periderm is common 

 in old roots yet none have it so well-developed as that observed 

 in the roots of Tr'ichosniilhcs cucwneroldes, T. japonica, and T. 

 muUiloba. 



Sclerenchyma. When the roots are young, sclerenchyma 

 is developed on the outside of each fibro-vascular bundle, but 

 when they become old it breaks up into several parts, often form- 

 ing two or three tangential parallel rows. When still further 

 advanced in age numerous masses of sclerenchyma are found 

 scattered in the cortex outside of each bundle as well as of each 

 medullary ray. The degree of development of the sclerenchyma 

 varies according to the species : some have well-developed and 

 numerous sclerenchyma groups, while in others they are delicate 

 and reduced. In Melothr'ia japonica, Irichosanthes cucumeroides^ 

 and Gymnosteinma clssokles the w^ell-developed sclerenchyma forms 

 a nearly continuous ring, but in Schizopepon bryoniœfoUus, var. 

 japonlcuSy Benincasa cerifera, and Cucurbiia Fcpo it is greatly 

 reduced. At the angled portions of old roots of Momordica 

 CJiarant'ia the sclerenchyma shows a charateristic double arrange- 

 ment like that seen in the old stem, a mass of it being developed 

 outside of each of the double fibro-vascular bundles heaped one 

 upon the other. 



Fibro-vascular BumUes. Most of the fibro-vascular bundles 



