85 



stylar partition maturing the embryo-sac somewhat earher than 

 those next in position, and these in turn earher than the follow- 

 ing and so on. If this should turn out to be the case, certain 

 ovules should be first prepared to attract the entering pollen 

 tubes on the theory that the direction of these is determined by 

 the presence of a stimulant which works chemotactically upon 

 them, a view advanced by Molisch and supported by my studies 

 of the Rubiaceae upon physiological-anatomical grounds. This 

 inference would have to be made in view of the fact that there 

 appears to be no special conductive tissue within the placental 

 parenchyma for the guidance of the tubes which, as above pointed 

 out, travel through it. 



The facts thus made out serve, to emphasize the contention 

 advanced by Murbeck, Longo and myself, to the effect that the 

 phenomena observed in the behavior of the pollen tube in the 

 various plants examined by us have a physiological meaning only. 

 This view is opposed to that which was previously advanced by 

 Treub and by Nawaschin, who ascribed rather a phylogenetic 

 significance to the matter. The fact that in widely different fam- 

 ilies, including the Rosaceae, Cucurbitaceae, and Rubiaceae, as 

 well as the so-called primitive dicotyledons, similar behaviors of 

 the pollen tube have been observed, loosens the grasp of those 

 who hope upon these grounds to construct a phylogeny of plants 

 of even the most crencral kind. 



CONTRIBUTIONS TO THE RECORDED FUNGUS AND 

 SLIME-MOULD FLORA OF LONG ISLAND 



By G. a. Reichling 



A list is given below, comprising a few additions to Dr. Jel- 

 liffe's Flora of Long Island in the fungi and myxonnxetes. 

 The specimens have been collected for the most part at Jamaica 

 and Flushing during last summer. Flushing seems to have a 

 particularly rich and interesting flora. 



In the list the nomenclature of Macbride is employed for the 

 myxomycetes. The localities are given with the names. 



