180 



Fam. IX. CYSTOSPERMEiE. 



Char. Filaments simple, subulate, non-conjugating. Cells at 

 first equal, subsequently here and there inflated or vesicular. 

 Sporangia formed by the union and condensation of the 

 endochrome of tioo contiguous cells of the same filament. 



The impression •whicli I first entertained respecting the Con- 

 fervcB contained in this family was, that it would be sufficient 

 to regard them as constituting a new genus, referrible to the 

 ConjugatecB already described : subsequent reflection and exa- 

 mination have, however, convinced me that they should hold a 

 higher than a generic rank, and that the characters presented 

 by them are sufiiciently distinctive to entitle them to the rank 

 of a separate family. 



Their filaments are simple, slightly subulate, owing to 

 the cells growing laterally, or in diameter as well as in longi- 

 tude, usually attached, do not conjugate, are articulated or 

 jointed, and terminate in lanceolate extremities: in their young 

 condition the cells are uninflated ; subsequently, however, cer- 

 tain ones swelled up, this inflation being occasioned by the 

 transference into them of the contents of one of the adjoining- 

 cells, and in these inflated cells, ultimately are formed, large 

 oval or circular bodies, similar to those of the Conjugatcce, both 

 in appearance and nature, and which therefore I in like manner 

 denominate sporangia. 



In addition to these essential characters of this family, the 

 CystospermecB are distinguished by other, though less obvious, 

 not less important characteristics. The filaments are of a 

 firmer texture than those of most other Conferva, they possess 

 comparatively but little flexibility, are not mucous, and con- 

 sequently do not exhibit that glossy appearance presented 

 by so many Conferva when removed from the Avater, and 

 which they retain when dried uj3on paper ; in all which par- 

 ticulars they stand in marked opposition to that numerous and 



