260 Macfarlane . — Observations on 
or runs straight up and again fuses into a recompacted midrib 
at the top of the pitcher. But the two genera differ in that 
the basal laminae of Heliamphora remain permanently as un- 
divided lobes, also the dorsal area between them and in front 
of the tube is reduced to a line so that the wings are thus 
brought close together and their surfaces stand out from each 
other at an angle of about 90° in seedling leaves, and nearly 
in line with each other in the adult. As we shall shortly see, 
the possession of these structural details causes Heliamphora 
to take a position intermediate between Nepenthes on the 
one hand and Sarracenia or Darlingtonia on the other, and 
this is further confirmed by the relative complexity of its 
glandular tissue. The lid, which in seedling leaves closely 
resembles that of Sarracenia rubra will be best understood 
after we have examined that genus. In Fig. 4 I have drawn a 
seedling leaf for comparison with that of the other genera. 
SARRACENIA. 
Like the last this is a genus of low growing plants pro- 
ducing similar rosettes of leaves. Six distinct species are 
known and in cultivation, S.jlava , 5 . Drummondii , S', rubra, 
S. variolaris , S', purpurea , and S. psittacina. A. de Candolle 1 
enumerates another two species, S. Sweetii and S. undulata , 
of which I can learn nothing. All the species, though differ- 
ing considerably in form, colouring, and histological details, 
exhibit fundamentally the same morphological type of leaf, 
and the leaves may or may not show pitchering of the midrib. 
S. jlava and S. Drummojidii , have pitchered and arrested 
leaves (Fig. 8) nearly in equal proportion ; the remaining 
four produce only or mostly pitchered leaves. 
Very diverse views have been advanced to account for the 
leaf form in the genus. St. Hilaire and Ducharte viewed the 
leaf as a pitchered petiole crowned by a lid representing the 
true leaf. Baillon 2 , after tracing the development of it, com- 
1 Prodromus, Vol. XVII (1873). 
2 Comptes Rendus, LXXI. 
