147 



logical features C. vnlcanica is much like C. didyina, and certain 

 writers still consider it a variety of that species. In 1931, however, 

 Robbins and Blake (12, p. 154) expressed the opinion that its 

 validit)' as a species should be recognized. The most important 

 difference between the two is chemical in nature. In C. didyma 

 there is no color change with potassium hydroxide and the reaction 

 with paraphenylenediamine is either wholly negative or causes a 

 pale yellow coloration. In C. vnlcanica, on the other hand, potassium 

 hydroxide gives a bright yellow color and paraphenylenediamine a 

 definite red, indicating the presence of thamnolic acid (see 26, p. 6), 

 as in C. macilenta. The New Jersey specimens of C. vulcanica may 

 be referred to the following form, in which the podetia are only 

 2.5-8 mm. in length : — 



9Aa.* Cladonia vulcanica f . minor Robbins ; in Robbins and 

 Blake, Rhodora 33: 154 pi 210, f. 7. 1931. AIgrris: Great Swamp 

 near Mt. Vernon. Ocean : Bamber Lake and Forked River. 



Subsection 2. Stramineo-floridae 



10. Cladonia pleurota (Floerke) Schaer. (25, p. 89). Ber- 

 gen : Allendale, Alpine, Bear Swamp Pond, Darlington, Emerson 

 (1938), Franklin Lake and Mills, Hohokus (1938), Mahwah 

 (1938), Paramus (1938), Ridgewood (1938), Saddle River {Mrs. 

 Dunham, 1939), Waldwick, Washington, and Wyckoff. Burling- 

 ton : near Red Lion (Dix, 1939). Essex : Cedar Grove and North 

 Caldwell. Hunterdon : Silver Hill. Mercer : Dutch Neck and Mt. 

 Rose. Middlesex : Rhode Hall and South River. Monmouth : 

 Ardena, Cranberry Hill, and Morganville. Morris : Great Swamp 

 near Mt. Vernon, Green Village, Littleton, Mt. Freedom, New 

 Vernon, Oak Ridge, and Waughaw Mountain. Ocean : Island 

 Beach (Dix, 1939), and Pasadena. Passaic: Bearfort Mountain, 

 Franklin Clove, Goffle Ridge and High Mountain near Haledon, 

 Haskell, Hewitt, Monks, and Mountain Glen Lakes near Upper 

 Macopin. Somerset : Lamington and Lyons. Sussex : Andover, 

 Colesville, Hamburg Mountain, Kittatinny Mountain, south of 

 Lake Hartung Road (1938), Rock View near Montague, and 

 near Sparta Lake (1938). Union: Fanwood and Seely's Glen. 



10a. Cladonia pleurota var. frondescens (Nyl.) Oliv. 

 (25, p. 90). Bergen: Darlington. Gloucester: Mullica Hill. 



