101 
annual rings are on the whole fairly distinet and the spring 
wood is differentiated from that of the summer. 
The roots have not been investigated. 
Fig. 17. Phyllodoce coerulea. 
Transverse section of stem. >< 180. (Greenland.) (Phot.) 
Cassiope tetragona (L.) Don. (Figs. 18—21.) 
Warmine, 1885, pp.53—54; 1887, p. 108. Linssauer. 1900. 
Borcesen, 1895, pp. 236—237. Amprony, 1890, p. 70. O.G. PETER- 
sen, 1901, p. 76. 
The specimens I have had for examination are from the 
following localities: — West Greenland: Tatsip-ata (July 15, 1884, 
Th. Holm); (Disco) Röde Elv (Porsild); Kekertat (Sept. 9, 1886); 
Pugtokortok (July 13, 1887, C. Ryder); Pröven (July 2, 1888, 
C. Myhre); Upernivik (July 11, 1886); tent 20 (Ryder); loc. ign. 
(July 14, 1884). East Greenland: Danmarks O (Nov. 6. 1881, 
