Fig. 3.

Flower morphological and ecological data summarized by flower type: 1, ‘small (horizontal)’ flower; 2, ‘large (horizontal)’ flower; 3, ‘medium-sized (horizontal)’ flower; 4, ‘locked (horizontal)’ flower; 5, ‘(large) vertical’ flower. (A) Length of fleshy staminode; (B) distance between flower entrance and nectar; (C) nectar concentration; (D) nectar volume. X, significantly different after non-parametric Kolmogorov–Smirnov test at a level of P < 0·01 towards floral types (see superscript numbers).