



THE DEHISCENCE OF ANTHERS BY APICAL PORES. 217 



Floral Ecology of Apically Dehiscent Forms. 



It was the similarity of adaptation which first aroused 

 interest in the morphological peculiarities described above. 

 We may now examine the data available upon these floral 

 structures regarded as adaptations. 



The ecology of the Araceous, Gramineous and Poly- 

 galaceous types is quite foreign to our present considera- 

 tions. That of the Ericaceous type has many points of 

 interest but material is not yet satisfactorily arranged for 

 a summarized statement and the individual data are too 

 numerous for consideration here. 



ECOLOGY OF DILLENIACEOUS TYPE. 



In the Dilleniaceae, Ducke saw Melipona bipunctata 

 abundant on an unidentified Tetracera at Para in Brazil 

 and also a small species of Halictus visiting the flowers of 



Da 



rugosa in great numbers. On S 



the 



interesting habit of producing inflorescences from the lower 



gions of the main stem h 



Knuth observed in J 

 flowers of 8. cauliflc 



the 



flogen 



mehrere 



mit grossen Ballen weissen Pollens wieder hervorkommend, 

 und auch kleine Bienen (Podalirius?) flogen ab und zu." 

 As a visitor of S. nudifiora he saw Podalirius clinging to 

 the flowers from below and diligently collecting pollen. It 

 is unfortunate that the evidence is so meager that one is 

 only able to surmise that these are pollen flowers, perhaps 



very similar to Rosa. 



Observations on the Elaeocarpaceae are of the character- 

 istic meagerness. According to Thomson, Elaeocarpus 

 Hookerianus of New Zealand has perfect, white, protan- 

 drous flowers in which a glandular ring at the base of the 

 stamens secretes nectar freely ; it appears to be entomophil- 





