22 



NATIVE BRITISH ORCHIDACE^ 



from the upper stigma, a female organ— the caudicles being at first free, but later 

 becoming attached. Thus one of the origiBal three stigmas actually provides the 

 mechanism for the transport of the pollinia to stigmas on another spike, and so 

 prevents them from reaching its sister stigmas. 



Sprengel spoke of Orchis morio and O. latijolia as " Scheinsaftblumen"— false honey 

 flowers— wliich entice insects by the promise of nectar which their dry and empty 

 spurs do not fulfil.' The spur, he said, was the true honey gland and also the honey 

 receptacle, but though he examined many flowers, he could find no honey. He con- 

 sidered that no honey could be secreted, as the inside of the spur was covered with 

 hairs, whereas nectar-secreting surfaces must be glabrous and smooth. The spurs of 

 Platanthera Morantha, etc., however, which contain free honey, have hairs on dieir 

 inner surface. Delpino^ spoke of the illusory spurs of 0. morio and other species of 

 Orchis as formerly melliferous but now dry— a sure sign, he said, of organic degenera- 

 tion whose pernicious effect was only too evident from the smaU number of seed- 

 capsules produced. He regarded 0. mascula, morio, etc., as on the verge of extmctionl 

 Darwin also examined all our common British species of Orchis and could find no 

 trace of nectar, and concluded that the spurs never contain any.3 He found, however, 

 that the spur had an outer and an inner wall, separated from each other to a surprismg 

 extent, that the inner skin was extremely delicate and could be penetrated with the 

 greatest ease, and that between the two membranes a quantity of fluid was contained 

 If the end of the spur be cut off and the latter gently squeezed, large drops of fluid 

 are exuded. He therefore concluded that insects pierce the delicate inner membrane 

 and suck the copious fluid. This was a bold hypothesis, for no case was then biown 

 of Lepidoptera4 penetrating even the most delicate membrane with the proboscis. 

 At the Cape of Good Hope, however, moths and butterflies do much damage to 

 peaches and plums by puncturing their unbroken skins. He observed that various 

 kinds of bees kept the proboscis inserted in the spur of 0. morio for a considerable 

 time and in constant movement. The same thing was noticed in the case of a fly, 

 Empis livida, on 0. maculata, and minute brown specks were sometimes seen on the 

 inner skin, where punctures appeared to have been made.5 Delpino^ said that Darwm 

 suggested that honey was secreted between the spur-walls. This was a misunder- 

 standing—Darwin stated quite clearly that he could find no trace of honey. Delpino 

 contended that the liquid between the spur-walls was not honey, but merely "Imfa" 



■ Sprengel, Das entdeckte Gehdmniss der Natur, p. 403 (i793)- 



; c£s stSS- m &M}l!^ora there is an abundant secretion of nectar inside the spur 

 (iLTiloVLi)). Also that in the Lizard Orchid, before the expansion of the flower, nectar is 

 secreted, but that it has almost entirely disappeared when the hp unrolls {ihd. p. 121). 



4 Some species of orchids are pollinated by butterflies. ^^ , ^. , , „^,v 



5 Ann. Naf. Hist. p. 145 (1869). ' Appar. d./econda^. «• pante (1867). 



