264 Macfar lane Observations on 
this dorsal downgrowth from the leaf apex in .S'. psittacina 
undoubtedly corresponds to the bilobed lip of Darlingtonia , 
so that, though S. psittacina appears to have no part corre- 
sponding to the lip of the latter, a cursory examination will 
prove that the two parts in question are the same. 
The genus Sarracenia then shows in a fully developed leaf 
a pair of basal sheathing leaflets of a delicate white or greenish 
white colour growing from the front of the midrib, a solid 
midrib prolongation destitute of lamina, at least for some 
distance, a pitchered midrib portion in front of which two 
elongated green leaflets have fused producing a prominent 
wing, a dorsal continuation of the pitchered midrib in flattened 
form which gives off on either side two leaflets, the whole 
constituting the lid, and finally, in some species, a filamentous 
midrib termination, which, by possession of a terminal pelta- 
tion, may indicate the incipient production of an additional 
leaf part. 
DARLINGTONIA. 
This genus is monotypic, D. californica being found in 
swamps in the Rocky Mountains. It agrees in habit with 
the two last genera. Having studied Sarracenia , the only 
part which calls for further notice is the leaf extremity. The 
ventral and ventro-lateral parts of the pitcher are greatly 
developed here in an overarching manner, and the associated 
vascular bundles, after ramifying over the arched portion, con- 
verge in the middle of the outer or ventral rim of the orifice. 
From this point the bilobed flap hangs as a dorsal develop- 
ment, and is abundantly supplied with vascular tissue. I have 
not been able to trace the number of bundles entering it at 
its attached base, but several sets radiate out in a bilateral 
manner on each side of its middle line, and these apparently 
result from branching of a smaller number at the base. The 
exact homology of it with the lid of Nepenthes is evident, 
but it also corresponds, as already noticed, to the area in 
S. psittacina , intervening between the organic leaf apex and 
the pitcher orifice on the ventral side. 
