62 MR. C. BAILEY ON THE STRUCTURE ETC. 



XV. The Roots. 



The roots are of great lengthy creeping in the soft black 

 mud of the bed of the canal ; they are given off from the 

 nodes in verticils. They are capillary, uniform in diameter, 

 even when nine inches long, tawny-orange in colour, and 

 I have not seen them branch. 



In internal structure they bear some resemblance to the 

 stems. There is a central channel surrounded by a mass 

 of elongate cells hexagonal in outline, smaller in size, and 

 witb thinner walls than those of the rest of the cells within 

 the cylinder. Outside this area is a row of cells whose 

 walls are darker coloured than any of the others (except 

 the cells which form the exterior of the cylinder), and 

 they so arrange themselves as to form a sheath round 

 the central cells ; from this row of cells numerous short 

 branches are given off wliich enclose intracellular cavities 

 similar to those in the stem, but much smaller and more 

 circular (see fig. 89) . These cavities are regularly arranged 



Fig. 89. 



in one series round the central mass, as in the stem, but 

 there are occasionally outlying cavities in the neighbour- 

 hood of the external orange-coloured cells, as shown in 



