416 -. DR. J. D. HOOKER ON THE ORIGIN AND DEVELOPMENT 
more evident cuticle to the whole surface of the cone, except over the gland, which now 
appears to be a secreting surface, and is rather pulpy or viscid. 
At the next succeeding period, when the whole body is about 2;-æ5th of an inch long, — 
a considerable further change has taken place (fig. 4). The contraction towards the middle - 
has greatly lengthened and forms a neck, which separates an elongated conical base (the 
future lamina) from an oblong terminal body (the future pitcher). The groove is still 
shallow on the intermediate portion (the excurrent midrib) and on the pitcher above it, 
but is deepened into a canal with incurved edges on the lamina below it. The gland is 
now å deep cavity, with a large quadrangular orifice, over which hangs the incurved apex 
(the lid of the future pitcher) of the original conical body. A vertical section (fig. 5) 
through the centre shows a narrow pale line ascending close to the dorsal margin, curving 
over the apex and terminating in the incurved apex; this line indicates the position of 
the future vascular bundles. At fig. 4 a minute conical body is seen at the base of the 
groove, and is a nascent second leaf. 
At the next following marked stage, the lamina, excurrent midrib, and pitcher are 
externally very well defined, and the lid of the pitcher differentiated. The lamina is still 
a cone, but much elongated, and presents a cylindrical groove with the edges slightly 
turned in, representing the earliest appearance of that organ in its involute condition of 
vernation. The contracted portion above it (the excurrent midrib) has elongated more in 
proportion than the lamina or pitcher, and its frontal groove is less marked. The apex of 
the pitcher has grown upwards and backwards ; the incurved portion, again, has so grown 
downwards as to close the orifice of the cavity. On a vertical section (fig. 7) the cavity 
is seen to be prolonged downwards as a sac parallel to the walls of the pitcher, whilst the 
incurved portion or lid has both grown downwards over the mouth of the cavity, and 
inwards towards its dorsal face; its protuberant inner surface is more papillose than any 
part of the sac, As the pitcher enlarges, the apex, which points upwards and backwards, 
elongates, at first considerably more than the lid itself, and becomes the styliform process 
at the junction of the lid and pitcher. On a vertical section (fig. 8) the vascular bundle is 
seen fo run up to the apex of this process, which thus continues to be the true organic z | 2 
apex of the whole foliar organ. E 
The succeeding stages of growth were examined in N. Rafflesiana and phyllamphora M 
and present few external characters but what have been previously observed. In ie 
former species the terminal process often spreads and divides, and, together with the Å = 
whole pitcher, is covered with appressed hairs. These hairs point upwards everywhere mes 
except on the young lid, where they either project or point in the opposite direction. On 
à vertical section at this time, the lid is found to have reached the lower portion of the 
orifice, and it afterwards closes the mouth of the pitcher (fig. 10) ; and one or two recur- 
rent fascicles of vessels are found to originate in the principal vascular bundle in its 
course towards the apex of the young styliform process, which bundles enter the sub- 
stance of the lid, and ramify in it. ES 
The vernation of the leaf in Nepenthes is well known to be involute, the opposite 
he. dm being ‚each rolled in towards the midrib. This curious arrangement, whichis ` 
no% peculiar to the genus, appears to me to be a secondary one, or rather an induced con- 
