60 



order to place a brief, compact and inexpensive means of identi- 

 fication of these northern species, upon characters observable 

 with the naked eye or a hand lens, in the hands of students who 

 are becoming interested in lichens as an extension of general 

 botany, on their rambles and vacation trips. 



The distribution of Cladoniae, as observed by this writer, 

 from New Jersey to Gaspe, and from sea level to over 5,000 

 feet, in the regions in which he has collected, suggests that they 

 are affected by the factors that influenced the migration of 

 vegetation northward after the close of the last period of glaci- 

 ation in North America, 30,000 to 50,000 years ago. Like alpine 

 and arctic flowering plants, they retreated northward, and in 

 many cases retreated upward to higher elevations in the areas 

 first uncovered by the melting of the ice sheet, where they are 

 now isolated on boreal islands. Northern species, such as 

 Cladonia deformis, still remain on some of the higher mountains 

 in the club range, as in the Catskills. Dr. Evans, in his "Cladon- 

 iae of Connecticut" reports the collection, in the highest parts 

 of that state, in the northwestern townships in the Taconic 

 mountains, of Cladoniae not found elsewhere in the state, but 

 commoner in northern New England. Many of the species com- 

 mon in the club range appear to be extending into the North 

 Woods, and a recent discovery by the writer, in the Pine 

 Barrens of southern New Jersey, of Cladonia santensis, hitherto 

 reported no farther north than Maryland and originally deter- 

 mined from South Carolina on the Santee Canal, suggests a 

 migration of southern forms northward along the coast strip, 

 as occurs with flowering plants. But some of the species here 

 listed from the North Woods have not been reported in the Club 

 range, although they may be left islanded on some of the higher 

 summits of the Blue Ridge or the Great Smokies, above 4,000 

 feet. 



Readers are referred to the earlier paper by the writer, for 

 the morphology of the genus Cladonia, or, for more detail and 

 technical treatment, to the authorities there cited. 



Key to Groups and Species 



In this key, species listed in the earlier paper by this writer, 

 as of the range of the Torrey Botanical Club, extending only 

 as far north as the Catskills and Taconics, which have been 



