A study in the Morphology of the Leaf, 243 
wings increase, and a two-lobed outgrowth appears above the 
oval depression (Fig. 3,/) ; this is the lid of the pitcher, which, 
growing larger, ultimately covers the mouth of the cavity 
(Fig. 4). It will be seen in the examples to be described that 
the clearness of marking of the two lobes varies, even in the 
same species ; but in the larger majority of cases it is clearly 
seen, and may usually be recognised even in the mature state ; 
it was this that attracted Griffith’s attention, and led him to 
suggest the comparison with Bauhinia . 
Now, isolated observations, such as the above, upon the 
leaves from a single bud, are insufficient to settle the question 
of first origin of this two-lobed lid, and of its relation to the 
apex of the leaf. A comparison was therefore made of nu- 
merous leaves, in various stages of development, of N. phyll - 
amphora , from the Glasgow Garden, and of N. distillatoria 
collected in Ceylon. In both these species the first stages are 
as above described. In N. phyllamphora , the lip of the oval 
depression becomes straight on the side nearer the apex (Fig. 
5, a), while the apex itself becomes broad and flattened 
(Fig. 5, b). This is the first step in the formation of the lid, 
though the two lobes are not yet to be recognised ; very soon, 
however, the flattening having increased, the apex ( ap ) and 
the two-lobed lid (p) are distinguishable (Fig. 6), becoming 
more clearly defined as the leaf grows older (Fig. 7). As 
before, the lid, retaining clearly its two-lobed character, covers 
over the cavity of the pitcher, while the growth of the apex 
frequently becomes irregular in this species, resulting in those 
variously laciniate spurs, which are easily recognised with the 
naked eye in the mature pitcher (Fig. 8). Meanwhile the part 
of the phyllopodium below the depression becomes differen- 
tiated into the pitcher itself (as Figs. 4, 8) and the basal 
expanded portion, while the intercalation of the tendril takes 
place subsequently. 
Turning now to N. distillatoria , the results are in the main 
similar, the first stages being as before (Figs. 9, 10) : the apex 
becomes flattened as seen in profile (Fig. 10), while the surface- 
view shows that the cavity is first overarched by a simple flap, 
