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evidently migrated northward along the warm coastal strip, in 

 the same manner as the numerous southern flowering plants 

 which are found in the flora of the coast strip and the Barrens. 

 They were Cladonia didyma, and Cladonia verticillata, in a form 

 with dense squamules sometimes almost covering the lowest 

 rank of cups. 



What is probably the sole occurrence of the Iceland Moss, 

 Cetraria islandica, in the Harriman State Park, and perhaps in 

 the Hudson Highlands, was re-discovered, in a very small col- 

 ony, at 1350 feet, on the Appalachian Trail, on Fingerboard 

 Mountain. Several more colonies of it were found on Schune- 

 munk, Mountain, west of the Highlands and higher, (1690 feet), 

 in addition to a small occurrence noted last year. 



Speculations as to the method of its establishment were 

 roused by discovery of a small colony of the tiny squamulose 

 lichen, Lecidea russellii, on a glacial boulder of Wallkill Valley 

 limestone, transported southeast by the ice into the Highlands, 

 and now used as a cairn on the Ramapo-Dunderberg Trail on 

 Fingerboard Mountain, in the Harriman Park. This species is 

 frequent on limestone ledges in western New Jersey and in 

 western Orange County, New York. It was found on Shenan- 

 doah Mountain, in Putnam County, N. Y. on a club trip last 

 April, probably on the ancient Grenville limestone. If it is an 

 exclusively lime-loving lichen, (although that is not certain, but 

 awaits later search) the problem of its transportation to the 

 limestone boulder in the park is stimulating. Was it transported, 

 in the form of its extremely minute spores, or in soredia or 

 thallus fragments on the feet of a bird. Or did it migrate from 

 one scattered Grenville limestone outcrop in the Highlands to 

 another, eastward to its present site, possibly along the retreat- 

 ing ice front of the Pleistocene continental glacier? We shall 

 look further to see if it is limited to limestone or may occur on 

 the pre-Cambrian granites or gneisses. The problem is like that 

 suggested by the rare occurrence of the usually, though not ex- 

 clusively lime-loving walking Fern, on glacial limestone bould- 

 ers, lying on granite, at Upper Cohasset Lake, in the Harriman 

 Park and near Sand Pond, north of Beaver Lake, in Sussex 

 County, N. J. But Dr. E. T. Wherry has reported the Walking 

 Fern on various other substrata than lime; I found it in Sep- 

 tember on Catskill sandstone on the Gulf Road, west of Watson 

 Hollow, in Ulster County. 



Raymond H. Torrey 



