In Phascolosoma and Phascolion this funnelshaped structure has broken up into a more or less definite group of tentacles, which in Dendrostoma are arranged in four groups.
In the terrestrial type a pair of well-developed wings traverse the length of the pitcher; in the tubular or funnelshaped form the wings are narrow or ridge-like.
It occurs in regions of granite, porphyry and syenite, and usually occupies funnelshaped cavities of no great superficial area, but of considerable depth.
Its summit comprises three groups of rocky peaks, of which the most westerly, Rucu-Pichincha (Old Pichincha), contains the crater, a funnelshaped basin 2460 ft.
Long jetties spring out on either side of the entrance, curving round about midway in order to run parallel to the river, thus forming a huge funnelshaped entrance; the eastern jetty forms a landing-stage for passenger traffic and the western is designed for the shipment of bunker and cargo coal.
The corolla is generally funnelshaped, more rarely bell-shaped or tubular; the outer face is often marked out in longitudinal areas, five well-defined areas tapering from base to apex, and marked with longitudinal striae corresponding to the middle of the petals, and alternating with five non-striated weaker triangular areas; in the bud the latter are folded inwards, the stronger areas being exposed and showing a twist to the right.