—45— 



some resisting medium is generally considered to be the cause of this enlarge- 

 ment, as seen in the disks at the ends of tendrils in such vines as Ampelopsis. 



If we regard rhizoids as organs for absorption as well as for holding a plant 

 in place, such expansions fixed to the cellular walls of mosses ought to help ma- 

 terially in taking up the moisture with which swamp mosses, especially Sphagnum, 

 are so well supplied. The water freely drawn up from below by capillarity, due 

 to the peculiar structure of the cells of Sphagnum and the arrangement of its 

 leaves and pendent branches, as obtained from rains and dews and held in storage, 

 would thus be at the more ready disposal of the scale moss associated with it. 

 Thus the rhizoid might prove to be of greater advantage as an organ for absorp- 

 tion than for mechanical support. It would be particularly serviceable to he- 

 patics growing under the conditions of those found in Bergen Swamp. They 

 were in the open and comparatively treeless portion of the swamp, much ex- 

 posed to sun and wind. 



The Sphagnum occurs in beds and hummocks, often but a few square feet 

 in area, the central parts raised a foot or two above the water table. They make 

 the beginning of a high moor formation. The surface of such beds is liable to 

 considerable dryness in the hot days of midsummer when the water of the swamp 

 is low or has wholly disappeared above ground. It becomes a trying season for 

 such delicate structures as scale mosses, but the closely fitting enlarged attach- 

 ment may help in making a more effective use of what water may be present 

 in the bed of Sphagnum. As the Lepidozia was found in a small oval or bossy 

 bed of this moss, the surface considerably desiccated in the August days, it 

 seemed to show a fitting adaptation to the environment. 



Chicago, III. 



* ADDITIONS TO THE LICHEN FLORA OF SOUTHERN CALIFORNIA 



NO. 7 



H. E. Hasse M. D. 

 Lecidea buUata Hasse n. sp. 



Thallus of a few small scattered ash colored squamules or absent. Apothe- 

 cia substipitate, scattered or four to eight grouped, from 0.5 mm. to 1.75 mm. 

 wide, the separate ones being the larger; disk dull black, faintly papillate, mostly 

 slightly concave, the larger slightly convex; margin thin, gray, or blackish gray, 

 entire or more or less sinuose, at times deeply, almost parting the disk into sev- 

 eral lobes; epithecium subcontinuous, bluish black to almost black, gradually 

 paling downward; thecium colorless (lower part), about ioo/a high; paraphyses 

 separate, stout, septate, branched, the rounded top clavate-thickened and not 

 or but slightly colored; hypothecium pallid brownish gray; asci long, com- 

 posed of an upper oblong-ovoid bullate expansion, 28/i to 36/i long, i2/x to 15/i 

 thick, contracting to a peduncle 60ju to 68/i long and 8^ to 9^ thick; spores ovoid 

 and oblong-ovoid, 8/x to i2/x long, 6ix to 9/x thick, simple, colorless; hymenium not 

 horny, with iodine staining blue to sordid greenish blue, the hypothecium greenish- 



