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ACOTYLEDOxNOUS PLANTS. 



The chief differences with Azolla, are the lobed nucleus in 

 both, even at a very early period, the development of gongy- 

 lus is observed in more than one lobe, and that not the central; 

 and the abortion of all the spores but one, that one being 

 surrounded by incrustation. 



In the other body, the only difference is the greater number 

 developed, and the cellular mature mass being one. 



On comparing the developments, it appears that the chief 

 difference consists in the original nucleus, and the prepondera- 

 ting development of one cell or spore, and the difform cellu- 

 larity of a definite number of the others. But in the abortion 

 of many, and the containing cells being fewer than they 

 ought to be, sufficiently marked agreements are to be traced. 



The order of Development is as follows. 



1. Cavity. 



2. Grume. 



3. Puncta. 



4. Division. 



5. Enlargement of nucelli, (spores) enlarge- 

 ment of Parent cell. 



6. Separation of spores, disappearance of all 

 the Parent cells. 



7. Appearance of secondary cells. 



The parts of the phenomena whose description has been 

 attempted, appear to me to be the following. 



The early structure of the bodies, (presenting an analogy to 

 the antitropous ovula) and the presence of grains in the neck 

 of the ovula, presenting analogies to fecundation. 



This will render necessary the consideration of the para- 

 physiform bodies. 



The development of the capsule and spores in Mosses, has 

 always appeared to me singular, but its extension to Azolla and 

 Salvinia (in a less complicated degree,) is an indication of its 

 generality among higher Acotyledonous Plants. 



The term, Capsula communis, is the most appropriate for 

 the outer covering of the organs both in Azolla and Salvinia. 



