Reproduction. 



65 



Close by this quadrat a retorio (plate 15, fig. B) was collected, which 

 had sprung from a lateral root 5 mm. in diameter. The chief shoot had 

 10 branches. Total height, 8.5 cm.; diameter at base, 5 mm. Number 

 of inflorescences 8, producing 80 to 120 seeds. 



Station 2 , quadrats 5 and 6 . Apr. 3 , 1 909. The following samples were 

 taken at random, supplying the attached data for growth in 1908 : 



From a bro ken-off tap-root 7 mm. in diameter, 2 new shoots, 12.5 

 and 13 cm. long by 6.5 and 7 mm. in diameter, respectively. 



From a broken-off tap-root 6 mm. in diameter, two new shoots 6.5 

 and 3 cm. long by 3.5 and 1 mm. in diameter, respectively. 



From a lateral root, a clump of 5 stems, each 2 cm. long. 



Experiment no. Station 3 (one quadrat). Dec. 31, 1907. 30 

 plants, 30 to 60 cm. tall, cut off with a talacho. No growth observed on 

 May 1 following, till which date there was no rain. July 16, 3 roots 

 had started. A number of roots, including the 3 which had started, 

 were taken up for examination and the data tabulated as follows: 



Table 24. Station 3 (exp. no). 



No. 



1 



3 



3 

 4 



5 

 6 



7 

 8 



9 

 10 



Order. 



Position. 



Secondary. 



Do. .. 



....Do. .. 

 ....Do... 

 Primary. . . 

 ....Do... 

 Secondary 

 ....Do.. . 

 ....Do.. . 



.Do. 



Nearly horizontal . 



....Do 



....Do 



....Do 



Vertical 



. . . .Do 



Horizontal 



45 



45 



Horizontal . 



Died back. 



> Failed to start. 



cm. 



25 

 13 



7-5 

 13 

 12 



3 

 20 



2.6; merely started 

 13; started; shoot 



2 . 5 mm. long. 

 2 io.5 



Diameter 



of root 

 where cut. 



mm. 



8.0 



4.0 



5-5 



ir 



17 



5 



4 



6 



1 Arising from No. 6 at 2 cm. from the top, where cut. 

 ! Started (in 1907 ?) shoot 7.5 cm. long. 



Experiment 121. Station 4, quadrat 1. 50 plants in all. These 

 were cut away as in the other experiments, Jan. 14, 1908. May 6, no 

 growth whatever apparent. A rain-gage was placed at this station on 

 Jan. 14. May 6: rainfall registered to this date, 1.52 cm. 



Apr. 5, 1909, 6 clumps of retofios. This appearance of new growth 

 followed on further rainfall, as evidenced by the rain-gage of Station 5, 

 a short distance away. 



Experiment 125. Station 5, quadrat 1. Jan. 15, 1908. 275 plants 

 cut off below level of ground with a talacho. May 6,30 roots have started, 

 sending up 1 to 5 shoots each, but smaller than those at Station 2 . Between 

 Jan. 15 and May 6, rainfall 353 mm. 



Apr. 5, 1909. 43 clumps of retofios. The increase in numbers was 

 the result of the additional rainfall, as indicated by the rain-gage, which 

 was still in position, though standing somewhat obliquely. Evidently 

 some of the water had been lost, as the oil had disappeared. The amount 

 remaining, 700 c.c, indicated a total precipitation of at least 850 mm. 

 Length of new stems, 7 to 15 cm., with diameter of 2 to 9 mm. 



Experiment in. Station 3. Dec. 31, 1907. 100 square meters. 

 30 plants cut off at surface of ground. No new growths till after May 1. 

 July 15, one retorio. Apr. 2, 1909, two retofios in all. 

 5 



