1 86 Alexander W. Evans, 



more or less to a certain scheme. The large interior cells of R. 

 floribunda are sometimes clearly visible through the small-celled 

 superficial layer, and in this respect recall the appearance presented 

 by R. Spegazsiniay]a, where the interior cells toward the margin 

 often surpass those of R. floribunda in size. Here again the 

 resemblance hardly signifies relationship. The thallus of R. 

 Spegassiniana is at once distinguished by its greater size and 

 regular pinnate branching, the short branches becoming more or 

 less subdivided in a definite manner. 



The inclusion of Ancura profunda among the synonyms of R. 

 floribunda is not wholly justified. The species was based on mate- 

 rial collected by Halle at Melinca, Guaitecas Islands, and was 

 described as sterile. Halle's specimens have not been seen by the 

 writer and his opinion of A. profunda is derived from the plants 

 collected by Skottsberg and received from Upsala and the Boissier 

 Herbarium. These plants clearly represent R. floribunda and agree 

 in a general way with Stephani's very brief description of A. pro- 

 funda, except that the contrast in size between the superficial and 

 interior cells is less marked than his measurements would indicate. 

 According- to his data the surface-cells are i8 /x, in width and the 

 interior cells loS/x, while the writer's measurements are 32 /i, and 

 75 «, respectively. Unfortunately Stephani's figure of A. pro- 

 funda, which represents the cross section of a primary branch, 

 does not support his description. It shows surface-cells which 

 equal or even surpass the interior cells in size and which (according 

 to his scale of magnification) have an average width of about 67 ix. 

 In view of the conflicting evidence it seems best to reduce A. pro- 

 funda to synonymy, at least provisionally, but to recognize the 

 possibility of its restoration to specific rank in the future. 



22, Riccardia tenax ( Steph. ) comb. nov. 

 Aneura tenax Steph. Bull. Herb. Boissier 7 : 755. 1899. 



Specimens examined: Puerto Angosto, Desolation Island, 

 1896, Duscn 7p5 (U., labelled Ancura tenax and listed under this 

 name by Stephani, 29, p. 9). 



The following additional records under Aneura teiuix may be 

 cited from the literature: Port Cook, Staten Island, Skottsberg, 

 and Ushuaia and Tekenika Bay, Tierra del Fuego, Skottsberg 

 (31, P- 2). 



