298 



BOTANICAL GAZETTE 



[APRIL 



millimeters of growth and the distance of the last mark from the 

 ground. As it grew 33 mm. and the last mark was 38 mm. from 

 the ground, the difference of 5 mm. might mean that three marks 

 had disappeared. If the first was at the base, the stretching, in 

 destroying these marks, could not have extended farther than 5 mm., 

 as the last mark visible was clear cut and 2 mm. from the one next 

 above it. The discrepancy was more likely to have been the 

 result of faultv measurements. 



. TABLE I 

 Region of growth in Scirpus validus 



Pot 



B 



B 



C 



C 



F 



F 



G 



G 



BB 



DD 



DD..;... 

 DD 



1 



Culm no. 



Marking 



To sheath 

 To sheath 

 To sheath ( ?) 

 To sheath 

 To sheath ( ?) 

 To sheath 

 Culm 

 Culm 

 To sheath 

 To sheath 

 Culm 

 Culm 



Region of growth 



No growth 

 Below top of sheath 

 Below top of sheath 

 No growth 

 No growth 

 Below top of sheath 

 Below last mark 

 Below last mark 

 Below top of sheath 

 No growth 

 Below last mark 

 Below last mark ( ?) 



Experiment 2 



February 191 5, n culms were marked, 6 to the top of 



sheath and 5 on the stem to the base. After a per 

 all marks were clear cut, and showed no separatio 

 mean that all growth took place below the last mark 



of growth 

 This may 



marks 



started 



this, experiment 



Experiment 3 



In March 1915, 4 culms were marked to the base, as just 

 described, and the number of marks counted. One culm did not 

 grow. In the second culm, after one day, the lowest mark had 

 disappeared; the second mark was 4 mm. from the base and was 

 perfectly clear cut. The other marks had not changed. In the 

 third culm, after 7 days, the first mark was at the base on a piece 

 of sheath; the second was clear and 13 mm. above the base. 

 In the fourth culm, after 7 days, the first mark was on a piece 





