134 



CUMMINGS 



chell) ; Port Clarence (Trelease, 1113, 1112, fragments with Cetraria, 

 etc.). Reported by Babington from Kotzebue Sound, by Nylander 

 for St. Lawrence Island; collected by Dr. Bean at Cape Lisburne, 

 Unalaska, and on logs in Cross Sound, and by Macoun on St. Paul 

 and St. George Islands. 



This species is represented entirely or in part by sixteen different 

 numbers, and exhibits great variation as to color of thallus and pres- 

 ence or absence of isidioid growths. The most normal forms are 

 represented by numbers 1113 and 1150. It will be noted that 1113 

 was collected at Port Clarence, the most northern station for this 

 species, and 1150 at Sitka, the most southern station. 



Numbers 11230:, 1066, and 1074 are characterized by a change of 

 color of a portion, or in 1074 of nearly all, of the thallus, to a reddish- 

 brown. Macoun notes the same fact in the following words : " Fre- 

 quently found abnormally colored from a red brown to a beautiful 

 violet." This is a change which often occurs in specimens of a normal 

 color which have been kept in a damp condition in a collecting 

 box for two or three days. Certain specimens, as NO. 368, show a 

 tendency toward the blackening which is characteristic of the variety 

 omphalodes. 



The most interesting variation, however, is that caused by the de- 

 velopment of the isidioid growths. This is only slightly evident in 

 H2ia and 1123, but very strongly developed in NOS. 368, Evans; 

 1515, Coville and Kearney ; 1 130 and 1 134^, Trelease. In these cases 

 the greater portion of the thallus, the periphery being excepted, is 

 densely covered with a growth which resembles minute specimens of 

 Sphcerophoron coralloides or Cladonia papillaria. This is the form 

 which Dr. Lindsay refers to as sph<zrophoroidea, in his Observations 

 on West Greenland Lichens, 328. None of the reddish-brown forms 

 show any isidioid growths. Macoun collected an isidiferous form on 

 earth on St. George Island. 



No. 1066 is interesting as showing the development of minute 

 secondary lacinia? upon the surface or at the edge of the lobes of the 

 thallus. 



Only two of the sixteen specimens bear fruit, or one-eighth of the 

 whole number, and the apothecia are poorly developed in these cases. 

 An examination of eleven specimens in my herbarium, including 

 material from Canada and Newfoundland, shows that six of the eleven 

 specimens (more than half) are fruited. The sterility of these Arctic 

 forms has been noted by Dr. Lindsay in his Observations upon the 

 Lichens of West Greenland. 



