FRESH-WATER ALO^E OF THE UNITED STATES. -JO.*) 



Godwinsville, New .l<r-r\." \-, dried, the plant is in extended, gray, felt-like 

 ma-M>. '1 he ualls of the articles as seen with the microscope are thick and 

 irregular, and the joints theiiiv l\es are also very irregular, the end ones being often 

 swollen and rounded M> as to give the branches a sort of bulbous termination. 



Among the Alga' collected in Texas by 1'rof. Ravenel, is a dried specimen (No. 

 100), labelled "On Bark, Houston, Texas," which I cannot separate from this 

 species. It occurs in small tufts, which, as dried, are of a very decided orange, 

 and, no doubt, were still brighter during life. The articles are not so irregular as 

 in Mr. Austin's specimens, but excepting in this and color when dried they agree 

 very well. Besides these I have several specimens from the game source, which 

 are in extended mats and agree in all respects with their northern brethren. 



Our American form appears to attain a greater diameter in its individual fila- 

 ments than does the European variety, but I know of no other character separating 

 it from the latter; and consequently must consider them identical. The measure- 

 ment given is an extreme one, .009" being commonly the limit. 



Genus BULBOTRICHIA, KUTZ. 



Filtt iiiili.-tinrtr urtirulata, achroa, finna, ramosa ; mini in apice intumesccntes, sporangia con- 

 tUtuentcs. 



Fil:iin< nis indistinctly articulate, translucent, firm, branched; the ends of the branches swollen so 

 as to form sporangia. 



B. albida, WOOD (sp. nov.). 



13. strato albido, coriaceo vel crustaceo ; fills arete intertcxtis, enormiter ramossissimis, coloris 

 expert il)iis; spojangiis viridibus. 



llab. In muscis, Northern New Jersey ; (Austin.) 



Forming a white leathery or crustaceons stratum ; thread closely interwoven, irregularly and 

 plentifully branched, colorless ; sporangia greenish. 



/,' murks. This curious little plant, which was sent me by Prof. Austin, occurs in 

 minute white patches growing on mosses at the base of stumps in woods. Some- 

 times tin -e are encrusted abundantly with the carbonate of lime, when they are 

 hard and crustaceous. The sporangia appear to vary greatly in size ; sometimes 

 they resemble very closely a single spore (probably their commencing stage). The 

 s of the branches are rarely, if ever, furnished with the bulbous swelling, given 

 by Rabenhorst as a generic distinction, but such enlargements do occasionally 

 occur in the course of the filaments and branches. The filaments are composed 

 of a series of cells, which are in places long, and have their end walls thin and not 

 readily seen. 



Fig. 5, pi. 16, represents a part of a plant magnified 460 diameters. 



FAMILY dLETOPHORACELE. 



Algae aquatics vel pnlustres, rarios terrestres, plcrnmqne monoicte vel dioicae. Fila varia, saepe 

 dichotomc ramosa, hund rnro fasciculatim ramnlosa, plerumque in caenpites vel pulvinulos curaulata, 

 in iniic-ii frcliitinoso aubliquido vel firmo nidulantia. Propagatio fit turn oosporia, tuin zoogonidiis. 

 Zoogouidia oriuuturaut singula aut gerainis aut cytioplasmatis divisione 8-16 in quoque sporongio. 



