454 The American Naturalist. [June, 



(No. 15). An old, much branched vine which has borne 

 fruit and is nearly past profitable culture. The principal 

 stem is 200 centimetres long (measured from the cut near the 

 earth) ; the longest branch is 105 cm. ; the next longest is 65 

 cm. The vine has lost much of its foliage but bears about 60 

 medium sized leaves (10 to 15 cm. broad) and as many more 

 smaller ones, mostly from short, lateral branches, so that the 

 transpiration on a sunny, windy day, like this, must be very 

 considerable. March 22, 2:05 p. m. The base of the vine, 

 which had previously been dug up carefully by the roots, and 

 put at once into water, was cut 30 cm. above the roots under 

 gelatine at a temperature of 40° C. 2:30 p. m. Many of the 

 leaves have begun to wilt, showing that the transpiration and 

 negative pressure must be very great. The stem was now 

 shortened under the gelatine one centimeter and the segment 

 examined. Most of the vessels were full of gelatine but not 

 all. A dozen or so of the pitted vessels were empty and more 

 than that many spirals. The vessels of some bundles ap- 

 peared to be completely full including the spirals. 2:40 p. m. 

 The foliage now shows a decided droop. Stem cut again 

 under the still fluid gelatine 4 cm. up. Fully one-third of the 

 pitted vessels are free from gelatine (contain air), but most of 

 the spirals seem to be full. The torn central stem cavity is 

 also full of gelatine and was in those examined yesterday. 

 3:30 p. m. Marked droop of all the foliage. Stem removed 

 quickly from the gelatine which has been kept at 40° C. and 

 plunged into water at 19° C. 3:50 p. m. Stem shortened 

 slightly and put at once into 1 per cent eosine water cooled 

 down to 14° C. An examination of the segment just removed 

 shows that nearly all of the vessels are full of the solidified 

 gelatine, but not all. 4:10 p. m. No trace of stain in any of 

 the leaves, although those nearest the cut are only 15 centi- 

 meters up. 5:00 p. m. The vine is drooping and needs water 

 badly, but can get none either through the walls of the vessels 

 or through the gelatine plugs. An hour and ten minutes has 

 passed since the stem was plunged into the eosine and yet 

 there is not a trace of stain in any leaf, although the eosine 

 water would have gone to the end of the vine and been dis- 



