122 



INTRODUCTION 



FiG- 33- Lister a ovata, L., an 

 Ichneumon Flower. 



agrees with the former species in the colour, form, and arrangement of its flowers, 

 only differing in that these are smaller. There is still, however, a necessity for 

 direct observation to confirm this supposition, since the agents which pollinate 

 Listera cordata are as yet unknown. 



The two species just named belong to the class of 

 flowers possessing exposed nectar, in connection with 

 which they have therefore already been mentioned. 



The very inconspicuous flowers of Chamaeorchis 

 alpina (Fig. 34) have also an incomprehensible attraction 

 for certain insects, for Hermann Miiller ('Alpenblumen,' 

 p. 74) found that in more than two-thirds of over fifty 

 specimens he examined with a lens the anthers were 

 empty and the stigmas pollinated. ' The small odourless 

 flowers are hidden under the low grass tufts among 

 which they grow, and which they somewhat resemble 

 in colour, and are actually so well concealed that to 

 avoid overlooking any of them, it is necessary to lie 

 prone on the turf in the place where they grow, inspecting 

 the sparsely covered surface with the greatest minuteness.' 

 From the flat, open position of the nectar, it follows that ' only tiny flies, beetles, or 

 hymenoptera can be considered as agents of cross-pollination, though these have not 



so far been observed. Of these 

 the most likely visitors are cer- 

 tainly the Ichneumons, judging 

 from their habits and the analogy 

 with Listera, and therefore Cha- 

 maeorchis alpina is probably to 

 be regarded as an Ichneumon 

 Flower.' (Herm. Miiller, Kosmos, 

 iii, 1878, p. 480.) Miiller subse- 

 quently placed this flower in 

 a special class, that of the Small 

 Insect Flowers (Sm) ('Alpen- 

 blumen,' p. 21). 



Numerous transitional forms 

 lead from Hymenopterid Flowers 

 to Lepidopterid Flowers. Such 

 intermediate types, which are 

 crossed both by bees (or humble- 

 bees) and Lepidoptera and which 



Fig. 34. Chamaeorchis alpina, Rich. (Ichneumon Flower?) may therefore be Symbolizcd by 

 B. A young flower after removal of the perianth except the ttut rri-T 



labellum (X 7). A. Middle of the same seen from the front (X35). HbL Or HhL, are Very mtCreStmg 



because they sometimes possess 

 two special openings, into which the proboscides of Lepidoptera and bees (or 

 humble-bees) can respectively be inserted. Rhinanthus Alectorolophus (Herm. 

 Miiller, 'Alpenblumen,' p. 290; Kosmos, loc. cit., p. 419), for instance, has a wider 



