496 Dr John Wilson on the [sess. liii. 



applies to the orange margins of the perianth lobes. The 

 furrows and ridges of the elevated radii (fig. 1, r) of the 

 stigma correspond with those on the face of the segments 

 opposite. The epidermis of the sulci is rendered detentive 

 by the papillie, a few cells high, universally distributed 

 there. The eight stamens (fig. 1, st) 'are situated beneath the 

 radii, that is, opposite the segments, and project nearly 

 horizontally from the wall of the cavity of the flower. The 

 whole stigma is rigid, in the newly-expanded flower, and 

 the incurved margins (fig. 1, c) are then so adherent to the 

 adjacent walls that an attempt to separate them leads to 

 rupture, and removal of a small triangular portion of stig- 

 matic tissue. In the flowers examined originally the stigma 

 exhibited no apertures leading into the cavity beneath. 

 The whole superficial tissue of the stigma and inner faces 

 of the perianth lobes is thickly beset with raphides, in all 

 probability to prevent surreptitious entrance by perforation. 

 The walls of the cavity are extremely smooth and glassy, 

 forming such a place as a slug might find pleasure in ex- 

 ploring. At an early stage the pollen, which is very 

 abundant and powdery, is shed, and rolls to the bottom of 

 the cavity (fig. 1, p). 



Looking at a case in which the stigma is imperforate, the 

 pollen cannot be reached until the stigma becomes flaccid 

 and free at the margins. In a certain time, dependent on 

 success of fertilisation and other causes, this takes place. 

 If a slug now enters, it cannot fail to have the greater part 

 of its body covered with pollen. It has been observed that 

 much pollen remained in (!ven very withered flowers. Find- 

 ing exit, and proceeding to a fresh flower, the slug will pry 

 about the sulci of the stigma and deposit the carried pollen 

 thei-e, thus performing cross-pollination. 



The belief that slugs are the agents employed in the 

 fertilisation of this species was strengthened by the discovery 

 of a few flowers with their small slimy visitants inside. 

 Jv\])eriments with the slugs did not demonstrate anything 

 beyond this, tliat tliey creep about the grooves in quest of 

 a liolc, and wlicii Ihcy find it (although small and even 

 artiiicially foiiiied I'or theui), tliey descend by it into the 

 cavity of the fiower. 



Since the above note was brought before the Society, 



