56 FRESH-WATER ALG.E OF THE UNITED STATES. 



composed of irregular filaments which are sometimes ag- 

 glomerated into globular masses. This structure is of great 

 importance since, in the perennial species, it is the part 

 which renders the plant able to persist. It is capable of 

 growth and of reproducing itself by sporules. 



The non-sexual form he calls Chantramia, and describes it 

 as composed of broad tufts of filaments each consisting of a 

 row of cells ramifying and producing sporules, altogether 

 analogous to those of the prothallium. Since this form can 

 reproduce itself through a number of generations it has long 

 been regarded as a distinct genus under the name of Chan- 

 tramia. 



That a larger non-sexual condition may exist, and that it 

 may be somewhat similar to Chantransia, may not be con- 

 tradicted, but that all the forms of Chantransia are condi- 

 tions of Batrachospermum can not be admitted. 



The sexual generation the author (Sirodot), describes as 

 including a vegetative structure composed of whorls and 

 of primary and of secondary prothalli; but the author 

 founds his primary divisions on the character of the tricho- 

 gyne, according as it is pedicellate or sessile; in the latter 

 case it may be ovoid or in the form of a club, or a truncated 

 cone. In the process of impregnation, the author maintains 

 the actual absorption of the wall of the trichogyne at the 

 point of contact with the cell- wall, the passage of proto- 

 plasm from the latter through the orifice thus formed and 

 the appearance of a septum at the base of the trichogyne 

 which separates the cystocarpic vesicle. The rejuvenescence 

 of the protoplasm at the close of impregnation imparts a 

 great activity to this cell which then begins to bud and to 

 produce the carpospores or oospores. 



Mon. Sirodot describes thirty-three native and exotic 

 species of JBatrachospermum. 



BATRACHOSPERMUM MONILIFOEME, Both. 



Very variable in size, from one inch to a foot in length, 

 clothed with a more or less firm gelatinous mucus ; violet, 

 fuscous, reddish brown, purple or bluish green, vaguely and 

 profusely branched ; articulations of the branches similar, 

 oblong-subclavate, the outer ones sometimes setigerous ; in- 

 ternodes naked or furnished with a few scattered accessory 

 braiichlets. 



Cellules measure about 10 /* by 20 yw. 



Syn. Conferva gelatinosa, Dillw. Batrachosperma ludibunda mon- 

 iliformia, Bory. 



In fresh, cool rivulets, in springs of rapid limestone waters 

 rarely in ditches. 



