THE COMMON PRIMROSE 



vincing evidence that it is especially adapted to 

 insects with long tongues, such as bees, butterflies, 

 and moths ; probably it is the last two mentioned 

 (Fig. 57, Plate 37) that are most desired, for, 

 although bees occasionally visit the flowers yet 

 their visits are not nearly frequent enough to 

 account for the large quantity of seeds produced. 



Also, the large pale-coloured corolla of the 

 primrose points to the conclusion that it is adapted 

 for nocturnal visitors ; moreover, the flowers mass 

 themselves against the dark green leaves and pre- 

 sent a bold show that is conspicuous even at night. 

 Figs. 57 and 58 (Plates i'] and 38) explain this 

 better than any description. The cowslip is more 

 often seen to be visited by diurnal insects, but, 

 nevertheless, it also probably depends chiefly on 

 nocturnal visitors ; for, although it cannot make 

 much display with its small corolla, yet it makes 

 up this deficiency somewhat by distending its 

 calyx slightly and developing it of a pale green 

 colour, sometimes almost white, so that the floral 

 mass then stands out boldly (Fig. 56, Plate 37). 



Both the coloured petals and the green sepals 

 of the primrose have united their lower parts and 

 thus form a double tube. The upper parts of the 

 petals spread out as a platform for the fertilising 

 insect to alight upon. There is only one way in 

 which the insect can reach the nectar, namely, by 

 inserting its long proboscis or tongue down the 

 central tube. In Fig. 59 (Plate 39) two primrose 

 flowers are shown, and it will be observed that in 

 the example on the left the centre of the flower is 



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