98 



lodes tomentella Miq. 



a woody plant which presents striking differences from Phyto- 

 crene , both in general mode of growth, and in the structure 

 of the wood. It is in the first place not a twiner but climbs, 

 feebly as it appears from specimens, by means of tendrils, 

 which occur singly at each node, the stiff, more or less erect, 

 and closely clustered stems forming a rather dense bush. As 

 to the size which the stems may ultimately reach I can give 

 little information, but it is probable that they never attain 

 any such considerable diameter as old stems of Fhytocrene\ 

 the largest /o^/e^-stems which 1 have seen have been but 1.2 

 cm. in diameter. Another difference lies in the fact that while 

 the leaves of Pliytocrene were alternate, that is, spirally ar- 

 ranged , they are with lodes opposite and decussate. As the 

 author has shown in the case of Phytocrene, the arrangement 

 of the leaves exercises a lasting influence upon the secondary 

 thickening; it will be therefore not without interest to ob- 

 serve in lodes whether the leaves , which are, so differently ar- 

 ranged, play a like important part in determining the anato- 

 mical character of the stem, which we are now to consider. 



On observing with a moderate magnifying power a cross- 

 section of one of the strongly elliptical internodes of lodes 

 tomentella^ made at a point where the maiimum diameter of 

 the stem is about 5 mm., the following anatomical features 

 may be readily seen. Surrounding the pith, which contains 

 peculiar structures, to which we shall later return, stand the 

 primary vessels, which, together with the first wide, pitted 

 ducts, form broad, distinct groups. These bundles, each of 

 which contains 3 — 12 rows of vessels, are arranged in such a 

 manner that they also form an ellipse , of which however the 

 maximum diameter corresponds to the minimum diameter of 

 the internode, as will be seen from PI. XVIII, Fig. 1. Im- 

 mediately surrounding these bundles is a well-developed, con- 

 tinuous zone of secondary wood (/•) which, in general appea- 

 rance, and in the arrangement of its elements, corresponds 



