344 



ciliar rays number from 3 to 5, usually 4 ; they may meet in 

 the centre of the root. The sieve-tissue, as is also the case 

 in many other species of Ranunculus^ has in its outer part a 

 large pentagonal sieve-tube wedged in between adjacent cells 

 of the pericycle. Upon the inner side of the leptome-mass a few 

 cambial divisions may be observed. The diameter of the root is 

 from 1"5 to 2 mm. In the present species no essential differ- 

 ences were observed in the roots from the different localities. 



The roots of the second order are very slender; 260 — 

 300// indiameier. The epidermis is collapsed and the exodermis 

 well-marked. The cortex is very lacunose with about five layers 

 of cells. Endodermis is thin-walled; the central cylinder diarch. 

 No thickened part occurred within the exodermis. Mycorrhizas 

 were absent; but it should be noted that in the material at 

 hand there were only a few roots of the second order, and it 

 is especially in the latter that mycorrhizas are found in the 

 other species. 



The rhizome. The outermost layer of the cortex together 

 with the epidermis, is often collapsed and suberized. The 

 cells of the cortex are elongated in a tangential direction ; 

 they contained much starch (middle of July). Hollstein records 

 that in the interior of the cortex a continuous phellogen is 

 developed which usually produces a layer of cork which sepa- 

 rates off' about V4 of the cortex. I have not been able to 

 observe anything of that kind in the rhizomes which I investi- 

 gated. The vascular bundles are placed in a circle and vary 

 in number from 5 to 10, and are of different sizes; some are 

 circular in form, others are elongated tangentially (Fig. o. A]. 

 Their course may be very irregular, usually they anastomose. 

 Each bundle has its own endodermis, which may be slightly 

 lignified; the cells of it also are tangentially divided; Cas- 

 pary's dots are often distinct (Fig. 5, B). There is a cam- 

 bium capable of division and the greater part of the vessels 

 in the strands and of the wood-parenchyma is of secondary 



