444 BOTANICAL GAZETTE [December 



mark. The male plants of Cutleria multifid 



female gametes 



rm 



identical with the form Falkenbergiana. Further, 

 from the zoospores of Aglaozonia parvula Church obtained plants 

 which, like the preceding, have the creeping platelike thallus of 

 Aglaozonia, but whose column ends at the summit in filaments (not 

 fascicled) which bear the male gametangia of Cutleria. The latter, 

 being entirely a new form and having never been obtained by any 

 previous investigators, may be designated as form Churchiana. 

 Finding that the female gametes develop parthenogenetically and the 

 zoospores of Aglaozonia produce Aglaozonia directly with no alter- 

 nating appearance of Cutleria, Church concludes that Cutleria 

 and Aglaozonia represent simply polymorphism due to environ- 

 mental conditions, especially such as changes in the temperature 

 of water. 



In 1898 Sauvageau (43) reported that he found in nature, 



adspersa, a number 



same 



forms 



Thuretiana and Falkenbergiana, which were evidently growing 

 side by side, at the same time, and on the same spot under similar 

 conditions. In the summer of 1898, Kuckuck (25) obtained in 

 cultures at the Helgoland Laboratory a number of young plants 

 germinating from the zoospores of Aglaozonia parvula. The young 

 plants had the characters of the form Thuretiana, and in his material 

 female gametangia of Cutleria were produced. Besides, some of the 

 plants produced a creeping disk, so that the whole structure 

 resembled the form Churchiana, but the form Falkenbergiana never 

 appeared. 



Sauvageau (44, 45) found 



Gulf 



Maroc 



remained 



nized. Sauvageau considers Aglaozonia melanoidea to be the 



adsp 



adspersa 



which he collected at Guethary (Basses-Pyrenees), he observed 

 that the female gametes did not attract the male gametes. The 

 female gametes germinated very readilv parthenosrenetically and 



