41 G Dr. J. E. Gray on the Arrangement of the Families 



" The endochrorne of the bulb soon becomes compact, and at 

 tlie same time little processes like those of (Edogonium are de- 

 veloped on the surface; and the wall itself becomes fissured, 

 apparently to admit the contents of the microgonidia. The 

 endochrome then acquires a membrane and appears as a perfect 

 spore." (Berkeley, Crypt, p. 156.) 



In the genera Ochlochcete, Bulbocha-te, and Coleochate, " the 

 setffi, when present, are rigid continuous tubes ; and the fruit, so 

 far as has been observed, is not contained within an original cell 

 of the filament, but each sporangium is in a new cell, formed, it 

 is true, by the elongation of an original cell, but subsequently 

 separated from it by a septum. This occurs in Tiresias [(Edo- 

 gonium), Bulbochate, and ColeochateJ" (Thwaites, in Harvey, Ph. 

 Brit. t. 226.) 



1. Bulbochate. [B, setigera, Hassall, t. 54. f. 1-4.) 



2. Coleochate. (C. scutnta, Hassall, t. 77. f. 6.) 



3. Ochlochcete {0. histrix, Harvey, Ph. Brit. t. 226) may also be- 

 long here; but the fructification is unknown. 



Chcetophora pisiformis is not congeneric with C. elegans, Ag. : 

 it has the fruit and setae of Coleochcete, from which it would seem 

 to be separated only by its erect, free, not adpressed filaments. 

 There can be little doubt, therefore, that Chatophora tuberculata is 

 equally a Coleochate. (Thwaites, in Harvey, Ph. Brit. t. 226, note.) 



Suborder II. Siphonomorpha. 



The plant a single, elongate, contiguous, tubular cell, more or 

 less interlaced, on which is developed a sporangium. The zoo- 

 spores are formed by the union of these two cells on the same 

 plant. 



Fam. 1. Vaucheriadese. 



Cell simple, tubular, with a distinct ovate sporangium and a 

 lateral process [antheridium) , which temporarily conjugates and 

 produces a globular zoosperm. (See Karsten, Ann. Nat. Hist, 

 viii. 1861, p. 86, t. 9 a.) 



1. Vaucheria. 



2. Saprolegnial 



Suborder III. Callomorpha. 



Plant consisting of isolated cells, separate, or simply cohering 

 together in elongated simple or branched threads. Cells rarely 

 conjugating. 



Mr. Berkeley justly observes "that Desmidiacese and Diato- 

 macese may grow for years without forming a spore, the propa- 

 gation being carried on meanwhile by mere division" (p. 116). 



