226 



RECEPTION OF FLOWER-SEEKING ANIMALS AT THE FLOWEK. 



resembles a sugar scoop; in the Brazilian Aristolochia labiosa (fig. 257*), there is 

 a broad heart-shaped expansion in front of the narrow entrance to the flower; in 

 Aristolochia cordata (fig. 257'') there is an elongated, flagelliform perch for the 

 flies; whilst in our own Aristolochia Clematitis (figs. 257^ and 257®) there is a 

 slightly excavated lip on which the midges can alight before entering the flower. 



A multifarious variety of arrangements is met with in the perianths of Orchids 

 and in the corollas of bi-labiate flowers for promoting access to the flowers. There 



Fig. 257. — Arraugemeuts for the reception of Insects at the entrance to tlie Flower. 



I Veronica Chamcedrys. 2 Qphryu comuta. 3 Corydatis lutea, from the front. 4 The same, from the side. * Galeopsis 

 grandijlora. ^Aristolochia labiosa. '^Aristolochia cordata. ^Aristolochia Clemutitis; the lowermost flower is faded 

 and has bent down, its lip is folded over the entrance to the flower. ^ Longitudinal section of a flower of Aristolochia 

 Clematitis ; within the enlarged cavity of the flower are two midges (Ceratopogon) temporarily imprisoned by the reversed 

 hairs of the tube, 'o Flower of Epipogium aphyllum. n Pollinia of Epipogium. 12 Column of Epipogium showing the 

 small heart-shaped rostellum. '3 Shows the pollinia of Epipogium attached by their sticky rostellum to a pencil, in 

 process of withdrawal, fl, ", 12_ is somewhat enlarged; the other figures natural size. 



are all sorts of lobings and sinuses, fringes, pegs, and knobs on the lower lip which 

 serve as landing-stages for alighting and as fulcrums for further explorations to 

 numerous flies, wasps, bees, humble-bees, and butterflies. In the noble Orchid 

 Phalcenopsis Schilleriana (cf. fig. 258^) the smooth and complex labellum has a 

 little projection not far from its point of attachment which resembles, and indeed 

 serves, as a footstool to the visiting flies. Behind the footstool is the column, the 

 apex of which is occupied by the anther, and whose lower portion is excavated into 



