BY A. G. HAMILTON. 763 



the style lengthens rapidly and the ring of hairs round base of 



stigma sweeps the pollen out of the anthers and pushes it out at 



the orifice of the tube. At this stage the tip of the tube is 



hidden behind the posterior petals. Insects visiting the flowers 



force the posterior lobes of the corolla asunder, and pushing 



against the top of the tube are invariably dusted with pollen 



hanging to the anther-hairs. When the anthers are emptied of 



pollen the style lengthens so as to protrude between the posterior 



corolla- lobes, and the stigmatic lobes open (fig. 5) and are then 



ready to receive pollen from insect visitants. Haviland describes 



the process in L. anceps, Thunb., L. gracilis, Andr., L. gihbosa, 



Labill., and L. debilis (5, p. 182). I do not, however, find 



the latter plant named in Baron von Mueller's Second Census of 



Australian Plants. Pollen is always found scattered all over the 



lateral and anterior petals. The latter acts as a landing-stage 



for visitors. 



PLANTAGINEffi. 



Plantago lanceolata, Linn. — Hermann Miiller (1, p. 503) 

 quotes Delpino's opinion that this species is a transitional form 

 between anemophilous and entomophilous pollen-bearing plants. 

 The latter observer in support of his theory describes three 

 varieties which he noticed. First, the tall scaped form with veiy 

 long and thin filaments; second, a hill-growing plant with shorter 

 scape, but still essentially anemophilous; third, a mountain form 

 with very short scape, short spikes and filaments, which were 

 much visited by bees which collected the pollen. He goes on — 

 "This therefore is a form of Plantago which hangs between the 

 anemophilous and entomophilous conditions, and is capable 

 of being fertilised equally well by the wind and by bees. If the 

 filaments became stiff and coloured and the pollen grains adhesive, 

 while the anthers lost their peculiar quivering, we should have 

 befoi'e us the passage from anemophilous to entomophilous 

 characters, the evolution of an entomophilous from an anemophi- 

 lous species. This hypothetical transition has actually occurred. 

 Plantago media is a form that has become entomophilous; the 

 filaments have become pink, the anthers are motionless, the pollen 



