556 The American Naturalist. (July, 
law than that governing the rapid upward movement of the 
transpiration water, i. e., that of surface tension or capillarity. 
o. 19). This was a large old vine, nearly destitute of 
leaves, the only large one being 8 centimeters below the cut 
stem. March 23, 4:06 p. m. The tip of this stem was cut 
under water and immediately transferred to 1 per cent eosine 
water. 4:15 p.m. No stain in the veins of the first leaf, 8 
em. from the cut. March. 25, 12:45 p. m. The leaf, 8 cm. 
from the cut end, is flabby and its veins show a very decided 
stain. Farther down there is no stain visible externally. The 
stem was now removed from the fluid and cut open for exam- 
ination. At5 cm. down there was a diffuse stain involving 
the whole stem, but it was not dense and the bundles were not 
deeper stained than farther down the stem. At10 cm. the 
sieve tube tissue was stained as well as the xylem and there 
was also a slight diffuse stain into the parenchyma, but the 
general tone of the stem remained green. At 20 cm. from the 
cut tip one of the 9 bundles (outer ring) showed nostain. No 
stain outside of the bundles. At 40 cm. from the cut all of the 
bundles showed the stain but in one (outer ring) it was much 
fainter than in the rest. The color was a decided pale red, 
including the whole of the xylem but not extending to any 
other part of the stem. At 80cm. down, the stain was restricted 
to 4 bundles (the whole of the xylem part) and was barely dis- 
cernable. At 85 cm. there was still a trace in these bundles— 
stain in the whole of the xylem and not brighter in the spirals. 
At 90 centimeters, and farther down, the stain was wholly ab- 
sent. 
This also proved a very instructive stem. The fact that at 
remote distances the stain was not restricted to the spiral ves- 
sels of the stem but tinged the whole xylem equally (the lig- 
nified walls) is very striking and decidedly different from the 
results obtained by passing the stain up the stem, in which 
case the spirals are stained ahead of the pitted vessels and are 
clearly seen to be the carriers of the eosine. In this case that 
portion of the stem in the fluid was not shriveled, probably 
because it was old and mousy 
