Chap. ILL BIGNONIACE,E. 87 



rather thick stick, and its petioles were brought into 

 contact with it, these curved round the stick, showing 

 that they have some degree of irritability. The 

 petioles also exhibit a slight degree of spontaneous 

 movement; for in one case they certainly described 

 minute, irregular, vertical ellipses. The tendrils ap- 

 parently curve themselves spontaneously to the same 

 side with the petioles ; but from various causes, it was 

 difficult to observe the movement of either the tendrils 

 or petioles, in this and the two following species. 

 The tendrils are so closely similar in all respects to 

 those of B. unguis, that one description will suffice. 



Bignonia unguis. The young shoots revolve, but 

 less regularly and less quickly than those of the last 

 species. The stem twines imperfectly round a vertical 

 stick, sometimes reversing its direction, in the same 

 manner as described in so many leaf-climbers ; and 

 this plant though possessing tendrils, climbs to a 

 certain extent like a leaf-climber. Each leaf consists 

 of a petiole bearing a pair of leaflets, and terminates 

 in a tendril, which is formed by the modification of 

 three leaflets, and closely resembles that above figured 

 (fig. 5). But it is a little larger, and in a young plant 

 was about half an inch in length. It is curiously like 

 the leg and foot of a small bird, with the hind toe cut 

 off. The straight leg or tarsus is longer than the three 

 toes, which are of equal length, and diverging, lie in 

 the same plane. The toes terminate in sharp, hard 

 claws, much curved downwards, like those on a bird's 

 foot. The petiole of the leaf is sensitive to contact : 



