170 IOWA ACADEMY OF SCIENCES. 



39. C. W. Sever, Cambriclg-e, Mass. 1886. Contains descriptions 

 of thirty-one common lichens. 



51. . On the Schwendener Theory of tlae con- 

 stitution of Lichens. Am. Mo. Mic. Jour. 8: 21-25. F 1887. 



52. . About Lichens, Pop. Sci. News 26: 50- 



52, 65-67. Ap, My 1892. (Illustrated Figs. 17.) A popular 

 article for beginners in the study of lichens. 



53. . A Key to the North American Species 



of Cladonia. Cambridge, Mass., 1893. A quarto blue-print. 



54. Schneider, A. A. Monograph of Lichens. Bull. Torr. 

 Bot. Club 21 : 492-493. 24 N 1894. A review of J. M. Crombie's 

 British Lichens. 



55. — . Contributions to Lichenology. Bull. 



Torr. Bot. Club 21: 532-534. 24 D 1894. A review of J. Reinke's 

 " Abhandlungen iiber Fletchen. " 



56. . The Biological Status of Lichens. Bull. 



Torr. Bot. Club 22: 189-198. 15 My 1895. 



57. . Some special Polygenetic Adaptations 



in Lichens. Bull. Torr. Bot. Club 22: 498-500. 30 D 1895. 



58. Stirton, J. Lichens, British and foreign. Trans. 

 Glasgow Soc. of Field Nature. 85-95. 1875. Mentions species 

 from Montreal and Lake Superior. 



59 Stitzenberger, E. De Lecanora subfusca ej usque formis 

 Commentatio, Botanische Zeitung 26: 888-902. 25 D 1868. 

 Mentions North American varieties. 



60 — . Notes on western Lichens. Erythea 



3: 30-32. 1 F 1895. Lists thirty-five Lichens from Yellow- 

 stone Park, Monterey & Sitka. 



61. Tucker man, E. An enumeration of some Lichens 

 of New England, with remarks. Boston Jour. Nat. Hist. 

 2: 245-262. 1839. Gives forty-three species and varieties. 



62. . A further enumeration of some New 



England Licheaes. Boston Jour. Nat. Hist. 3: 281-306. 18 H. 

 Gives sixty-eight species and varieties. 



63. . Further notices of some New Eagland 



Lichenes. Boston Jour. Nat. Hist. 3: 438-448. 1841. Gives 

 twenty-six species. 



64. . A further enumeration of some Alpine 



and other Lichenes of New England. Boston Jour. Bot. 

 5: 93-104. Ja 1845. Giv^es thirty-one species. 



65. . Lichenes Americani septentrionalis 



exsiccati. Fasc. I-VI. Cambridge and Boston. 1847-1854. 



