14 ARKIV FÖR BOTANIK. BAND (S. N:0 4. 



maculis striisve albidis parcius instructus. Tliallus casta- 

 neus aut partim spadiceus, basin versus et partibus umbro- 

 sis pallidior, qua nota, sicut etiam maculis albidis differt 

 ab A. nitidula (Th. Fr.), quae thallo haud maculato, 

 olivaceo-nigricante, basi nigrescente instructa est. Thallo 

 maculato, apicibus sensira attenuatis, haud spinulosis a 

 Cetraria aculeata differt. 



Ad terram arenosam et inter alios lichenes prope pagum 

 Pitlekai haud minus frequenter, quam f. typica hujus spe- 

 ciei. Ster. 



2. A. nigricans (Ach.) Nyl., Lieh. Scand. (1861) p. 71,. 

 Lieh. Lapp. Or. (1866) p. 112, Lieh. Middendorff. (1874) 

 p. 4, Enum. Lieh. Fret. Behr. (1888) p. 7, 44, 53, 62; Th. 

 Fr., Fl. 1861 p. 410, Lieh. Spitsb. (1867) p. 10, Lieh. Scand. 

 (1871) p. 22, On Lieh. Engl. Pol. Exp. (1879) p. 351; Norrl., 

 Berätt. Torn. Lapp. (1873) p. 321; Almqu., Lieh. laktt. Sib. 

 (1879) p. 35, 37, 38, 40, 41, 46, 47, 50, Lieh. Kust. Be- 

 ringsm. (1887). p. 521, 522, 523, 524, 535, 541; Wain.,Adj. 

 Lieh. Lapp. I (1881) p. 116, Lieh. Sibir. (1896) p. 5, Lieh.. 

 Exp. Amdrup (1905) p. 126; Stizenb., Alect. (1892) p. 121; 

 Cumm., Lieh. Alaska (1904) p. 138. Cornicularia ochro- 

 leuca ß. nigricans Ach., Lieh. Univ. (1810) p. 615. Alec- 

 toria Koerb., Parerg. Lieh. (1865) p. 5; Tuck., Syn. North 

 Am. Lieh. (1882) p. 45; Rothr., List Lieh. Alask. (Proceed.. 

 Un. St. Nat. Mus. 1884, VII) p. 2. A. Thulensis Th. Fr., Lieh. 

 Suee. Exs. (1860) n. 28, Lieh. Aret. (1860) p. 28; Deichm. 

 Br. et Groenl., Groenl. Lich.-Fl. (1888) p. 465. 



Var. Thulensis (Th. Fr.) Wain. Alectoria Thulensis 

 Th. Fr., 1. c. 



Thallus basin versus plus minusve late pallidus, apicem 

 versus nigricans vel livido-nigricans, maculis elongatis augustis 

 albidis, totus opacus; partes palhdae KHO leviter luteseentes, 

 CaCloOj leviter rubescentes, at his reagentiis unitis intense 

 rubescentes; partes nigricantes neque KHO, nee CaCl.jOj di- 

 stincte reagentes. 



Ad terram arenosam et supra alios liehenes ad lapides 

 prope pagum Pitlekai, in peninsula Jinretlen et in littore 

 orientali sinus Koljutschin. Ster. 



Var. Tschuctschorum Wain. 



Thallus nigricans aut oHvaeeo-nigricans, basin versus an- 

 guste paUidus aut olivaceus, maculis elongatis augustis albidis. 



