4o8 



ANGIOSPERMAE—MONOCOTYLEDONES 



to burst, when the mucilage exudes. This fixes the caudicles to the fore-part of the 

 insect's head, so that the pollinia are drawn out of their recesses. In order to prevent 

 tearing of the pollinia, which are firmly surrounded by the anther lobes, the original 



tip of the anther is situated on the rostellum. 

 When the insect has come into contact 

 with the epidermis of the latter, and the 

 caudicles have become fastened to its head 

 by means of the sticky exuding secretion, 

 it immediately strikes against the tip of the 

 anther in raising itself erect. This is thus 

 slightly raised, forming a broader cleft, 

 wide enough for the pollinia to be drawn 

 out uninjured. As the insect leaves the 

 flower immediately after removing the pol- 

 linia, an extremely rapid hardening of the 

 adhesive liquid is necessary in order that 

 they may not be torn from the insect's 

 head as it flies. 



Both pollinia are usually removed 

 simultaneously by the visitor ; should one, 

 however, remain in its recess, polUnation 

 is not prevented, as a small part of 

 a pollinium is enough to effect it. The 

 pollinia chng between the eyes and the 

 forehead of the insect ; their caudicles are 

 extremely slender, and are drawn down 

 by the weight of the pollen until they lie 

 flat on the insect's head, the pollinia thus 

 projecting forward like a pair of club- 

 shaped feelers. On visiting another flower, 

 the insect bends its head slightly outwards 

 towards the nectary and brushes against 

 the projecting stigma, so that a part of 

 the pollinia remains clinging to it and 

 pollination is eff'ected. 



Fig. 377. Epipogum aphyllurtl^ Siu. (after 

 Pfit2er). A. Entire plant. B. Flower in longi- 

 tudinal section. C. Column in longitudinal sec- 

 tion. D. Pollinia. 



824. Limodorum L. 



2632. L. abortivum Sw. (= Orchis abortiva Z.). (Pedicino, Rend. Ace. sc, 

 Napoli, xiii, 1874, pp. 118-20; Freyhold, Verb. bot. Ver., Berlin, xix, 1877, 

 pp. 23-8.) — Pedicino states that automatic self-pollination takes place regularly in 

 this species. On a garden specimen Freyhold observed only closed flowers, which, 

 however, were otherwise normal in form and colour ; these fertilized themselves and 

 also set abundant fruits. The plants growing wild in the neighbourhood of Freiburg 

 i. B. seemed to behave similarly. On this plant, which is remarkably rich in pollen. 



