Fig. 2.

Linear regression between flower handling time and proboscis length of Prosoeca sp. on flowers of Lapeirousia oreogena divided into three successive phases. In addition, for each phase, illustrating pictures are given above: a, d hovering fly with proboscis in feeding position; b, e drinking with proboscis fully inserted into the flower spur with the head in contact with the anthers; c, f proboscis is removed in a rapid movement. Of these, only drinking time shows a positive relationship to proboscis length