18 RAYMOND J. POOL 



for many months. This condition presents a curious appearance 

 with the top-heavy plant high in the air connected to the soil only 

 by the naked skeleton below. Living green branches of this sort 

 are reported to have maintained such an independent existence 

 above the dead skeleton for as long as fourteen months. 



The same author reported^- ^ that in some cases such isolated 

 branches which had had no water for a year have produced flow- 

 ers. MacDougal considers that this phenomenon is in accord 

 with many other observations that approaching dissolution often 

 stimulates the reproductive processes. 



In April, 1914, MacDougal superintended the collection of a 

 branch of the Sahuaro and the shipment of the same from Tuscon 

 to the department of botany at the University of Nebraska. The 

 specimen was started from the desert on April 19 or 20 and 

 reg,ched Lincoln on April 27. The branch which had been neatly 

 cut away from the main trunk was about 8 dcm. long, slightly 

 curved and at the time of shipment was provided with several 

 swelling flower buds. The behavior of this isolated branch is of 

 interest in connection with previous studies of this species some 

 of which have been briefly noted above. 



The excised branch was carefully unpacked in the greenhouses 

 of the department of botany in the presence of what Professor 

 Bessey characterized as "an admiring throng." At that time it 

 was noted that several of the larger flower buds had been injured 

 in transit and had fallen off. However the branch still retained 

 one large bud which appeared to be normal and which gave 

 promise of opening within a few days. The branch with its 

 single precious bud was erected in a large earthen flower pot and 

 the lower part was covered with dry sand to a point well above the 

 scarified end. The whole preparation was then placed upon the 

 driest, sunniest, and hottest bench available in the greenhouses. 



The first large bud opened early on the morning of May 5 and 

 remained open only the one day since the weather was clear and 

 warm and under these conditions it was found that the flowers 



^ The water-balance of desert plants. Ann. Bot. 26: 71-95, 1910. 

 ^ The water-balance of succulent plants. Carneg. Inst. Wash. Pub., No. 141, 

 1910. 



