A SENSITIVE PLANT. 199 



hole without any appearance of the nervousness which 

 seems hereditary in English horses, partly due, I 

 suppose, to the unnatural conditions in which they 

 live. With every confidence in animal sagacity, but 

 none whatever in the stability of the bridge, I thought 

 it judicious on my return in the evening to recross it 

 on foot. 



I found two or three curious plants not before seen 

 on the rocks here, and again found the singular 

 Zygophyllaceous shrub Porliera hygrometrica, which, 

 is not uncommon in this part of Chili. The numerous 

 stiff spiny branches diverging at right angles must 

 produce flowers during a great part of the year, as I 

 observed at this season both nearly ripe fruit and 

 flowers in various stages of development. The small 

 pinnate leaves, somewhat resembling in form those 

 of the sensitive plant, have something of the same 

 quality. But in this case the effective stimulus seems 

 to be that of light, causing them to expand in sun- 

 shine and to close when the sky is covered. If at all, 

 they must be very slightly affected by contact, as I 

 failed to observe it. If I am correct, the appropriate 

 specific name would be pJiotoinetrica rather than 

 hygrometrica. 



In the hedges and among the bushes a pretty climb- 

 ing plant {Eccrejnocarpus scaber) seemed to be common 

 on the right bank of the stream, producing flower and 

 ripe fruit at the same time. It belongs to the trumpet- 

 flower tribe [BignoniacecB), though not rivalling in size 

 or brilliancy of colour the true Bignonias which I 

 afterwards saw in Brazil. 



Having passed on the left the opening of a narrow 



