Bryological Notes.— I 



By Elizabeth G. Britton 



Didymodon riparitts Aust. — This species was described as Potha 

 riparia Aust. in the Supplement to Sullivant's Icones in 1874, and 

 the fruit was figured on Plate 21. In 1880, Warnstorf described 

 Barbula li)igitlata y which Limpricht later changed to Trichostomum 

 Warnstorfii (Laubm. I : 587. 1888) the specific name being pre- 

 occupied. In 1892, Kindberg in Macoun's Catalogue, described 

 Leptodontinm Canadense, as a new species, remarking that "it is 

 rather peculiar that this genus had not been represented before in 

 North America." In the Bryineae of Europe and North America, 

 he redescribed this species as Didymodon Macoiuiii Kindb. (new 

 name) and referred Pottia riparia Aust. to Didymodon riparius 



, the name it bore in Austin's herbarium. I have critically 

 compared all these specimens and am persuaded that they are one 

 and the same species, characterized by very peculiar brood-bodies, 

 borne on long slender filaments, either in clusters in the axils of 

 the leaves or at the summit of the stems, mixed with the arche- 

 gonia and seeming to replace the paraphyses. Limpricht figured 

 them on page 588, Fig. 171 of the Laubmoose, and Correns in 

 Untersuchen der Laubmoose has also figured and described them 



Aust 



his 



as Trichostomum Warnstorfii. The European specimens have 

 not been found fruiting, and Austin's station on the Palisades is 

 the only one thus far discovered where it is known to fruit. It 

 has probably been overlooked in many places, on account of its 

 small size, dirty appearance and sterility. The following stations 

 are recorded for North America : On rocks in streams, Palisades 

 of northern New Jersey and southern New York, C. F. Austin ; 

 Niagara Falls, F. Wolle ; Watkins ; Chilson Lake ; Mrs. Harris, 

 Bashbish Falls, R. S. Williams. Penna.: Bethlehem, Rau and 

 Wolle; Pocono Mt, T. C.Porter; Springfield, Ohio, Miss Bid- 

 dlecome ; Owen Sound, Ont, J. Macoun. In Europe it is only 

 known in Switzerland from the Rhine at Schaff hausen and in the 

 lake at Zurich. 



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