49° The Ohio Naturalist. [Vol. IX, No. 6, 



forms, development of woody stems, development of the annual 

 habit, development of epigA^ny, development of cyclic flowers, 

 coalescence of the perianth or of other organs, decrease in the 

 number of floral parts, development of zygomorphy, increase or 

 decrease in the number of ovules, the presence of alternate and 

 opposite leaves, development of geophily, development of the 

 various kinds of fruits, extra-floral nectaries, and a host of other 

 important or trivial characters both morphological and 

 physiological. 



' In the present attempt sixteen great phyla have been recog- 

 nized. Recently Besseyt has published a paper entitled "A 

 Synopsis of Plant Phyla" in which fifteen phyla are proposed. 

 In general it may be stated that the writer agrees with Bessey's 

 scheme and as far as possible his names have been adopted in the 

 present paper. The sixteen phyla are as follows: 



SCHIZOPHYTA MyCOPHYTA 



Myxophyta Bryophyta 



DiATOMEAE PtENOPHYTA 



CONJUGATAE CaLAMOPHYTA 



GONIDIOPHYTA LePIDOPHYTA 



Phaeophyta Cycadophyta 



Rhodophyta Strobilophyta 



Chareae Anthophyta 



It will be seen that a uniform system of group endings is 

 maintained except for three phyla each of which is represented 

 by a single class. At present the writer is not prepared to give 

 these groups distinctive names, although uniformity would have 

 its advantages. 



Although the Diatomeae and Conjugatae are commonly 

 united as one phylum, there are fundamental differences between 

 them which have not been cleared up satisfactorily and until 

 further knowledge of their cytology is obtained a final union is not 

 advisable. The fifth phylum, the Gonidiophyta (gone, genera- 

 tion and dim. term, idion, gonidium, a zoospore) includes all the 

 green algae except the Conjugatae and Chareae, besides two 

 classes of fungi, the Archimycetae and Monoblepharideae. The 

 name, Archimycetae, should more properly be spelled Archaemy- 

 cetae or simply with an e. This group connects with the lower 

 green algae while the Monoblepharideae are closely related to the 

 Siphoneae. Almost all of the Gonidiophyta, as the name indi- 

 cates, are characterized by the presence of zoosporesr The 

 Chareae have practically nothing in common with the red algae. 

 Their affinities are probably with the green algae but so far 

 removed that thev are here regarded as an isolated phylum. 



t Univ. studies 7: 275-37:5. 1907. 



