SEETULARIA. 195 



■with the pre-ordination of nature, may be subject to such disturbance as 

 perplexes us by apparent anomalies. 



Some of these are beyond solution, or they lead to intricate discus- 

 sion. 



For the purpose of investigating the vegetative properties of this Ser- 

 tularia, a specimen five inches high was sundered on May 26, at a point 

 of the stem where it seemed tubular and empty. 



The upper half, A, Plate XXXVIII. fig. 11, was now inverted, while 

 the under half, B, remained erect, as in its natural position. 



The higher part of A, which before inversion was the lower as fav 

 as c originally, shot a new generation, c b, upwards, June 13, which 

 would have descended, had the natural position been preserved. At the 

 same time, B, fig. 12, retained in its natural position, had generated the 

 vertical shoot, c b, in the natural direction. 



Thus were there two vegetations in opposite directions from the same 

 point of the stem. They continued advancing nearly at an equal rate ; 

 but the vigour of B, kept in the natural position, surpassed that of A, 

 which had been inverted, in the ultimate number of parts ; for the por- 

 tion c ^ of B no longer than as represented, fig. 12, on June 13, had become, 

 on December 13, as c b, c a, c d, by new accessions. — Fig. 13. 



On June 7, or twelve days after bisection of the stem, a very minute 

 hydra issued from the lower twig of the natural regeneration, c b, fig. 12, 

 which animal had been brought to maturity by this interval. 



A new generation afterwards issued by descent from B, fig. 12, five 

 months subsequent to the section, so that, on November 9, it was repro- 

 ducing from both extremities. — Fig. 14. 



One of the lateral shoots of this descending vegetation bore a young 

 twig or upright stem, a, b, half an inch high, whereon three prominences, 

 denoting incipient cells, were evident, October 31. These amounted to 

 six on November 4, four being on one side and three on the other : eight 

 on November 7, divided as five and three, and on the ninth, there were 

 ten, divided as six and four. — Fig. 15, enlarged. On November 13, they 

 amounted to fifteen, divided as eight and seven ; twenty one on the 22d, 

 divided as eleven and ten ; besides which, a branch with four cells had 



