196 CONCLUDING REMARKS. Cuap. V. 
genus Mikania, there are leaf-climbing and twining 
species. The leaf-climbing species of Clematis are 
very closely allied to the tendril-bearing Naravelia. 
The Fumariacee include closely allied genera which are 
leaf-climbers and tendril-bearers. Lastly, a species of 
Bignonia is at the same time both a leaf-climber and 
a tendril-bearer; and other closely allied species are 
twiners. 
Tendrils of another kind consist of modified flower- 
peduncles. In this case we likewise have many in- 
teresting transitional states. The common Vine (not 
to mention the Cardiospermum) gives us every possible 
gradation between a perfectly developed tendril and a 
flower-peduncle covered with flowers, yet furnished with 
a branch, forming the flower-tendril. When the latter 
itself bears a few flowers, as we know sometimes is 
the case, and still retains the power of clasping a 
support, we see an early condition of all those tendrils 
which have been formed by the modification of flower- 
peduncles. 
According to Mohl and others, some tendrils consist 
of modified branches: I have not observed any such 
cases, and know nothing of their transitional states, 
but these have been fully described by Fritz Miller. 
The genus Lophospermum also shows us how such a 
transition is possible; for its branches spontaneously 
revolve and are sensitive to contact. Hence, if the 
leaves on some of the branches of the Lophospermum 
were to abort, these branches would be converted 
into true tendrils. Nor is there anything improbable 
