FLY FLOWERS 



127 



Hawk-moths (Macroglossa) are peculiar in the fact that they visit flowers in 

 bright sunshine. It is therefore not surprising that in the Alps, where Lepidoptera 

 abound, undoubted diurnal Hawk-moth Flowers have been evolved, such as Gentiana 

 bavarica and verna (Fig. 39). 



8. Fly Flowers (F). 



Fly Flowers, which are chiefly visited by flies (Diptera), do not constitute so 

 clearly defined a class as those in which Hymenopterid and Lepidopterid flowers are 

 respectively placed. They include species that are oecologically very diverse, and 

 are in fact divided into five sub-classes : (a) Nauseous Flowers ; {b) Pitfall Flowers ; 

 (c) Pinch-trap Flowers ; (d) Deceptive Flowers ; and {e) Hover-fly Flowers. 



A. Nauseous Flowers (Fn). 



So far as concerns concealment of nectar, the plants here included mostly belong 

 to the classes in which this is exposed or partly concealed. They are dull and often 



Fig. 40. Saxifraga bryoiJes, L., a flower belonging to Class EF. (After Henn. Miiller, 

 ' Alpenblumen,' p. 39.) 



spotted, and yellowish or dark purple in colour. By their nauseous odour they 

 attract many insects, especially carrion-flies and dung-flies, which are the active 

 agents of pollination. As already mentioned (p. 109) Hermann Miiller includes in 

 this group numerous species of Saxifraga, in which the whitish or yellowish and 

 often spotted flowers attract numerous flies, and he employs AD [=EF] as a group 

 symbol for Fly Flowers with exposed nectar (Fig. 40). Veratrum and Lloydia, and 

 perhaps also Rhamnus, Alchemilla, and others, are also to be included here. 



