Scrophulariaceae. 467 



und meidet sogar die sonnig trockene Wiese"; the species is 

 otherwise characterized as "håufig in der Heide, insbesondere 

 die frischere Andromeda-H., gem in schattigen, schneereichen 

 Mulden, vom Plateau das Gebirge emporsteigend, Ferner in 

 der Sumpfwiese und auf den Moorhiimpelen, aber einerseits 

 ins Moor nicht hinabsteigend, anderseits nicht auf trockener, 

 vegetationsarmer Felsenflur. Ein verfilzter Humusboden ist 

 unbedingt notvendig." In Greenland this species is a decided- 

 ly spring-flowering plant, but, as an exception, flowering 

 specimens may be found throughout the summer according 

 to the point of time at which the snow melts at the place 

 in question. Hartz found it on Danmarks with the flowers 

 still in bud on the Ist of September, and expressly remarks 

 that it was "on quite recently-bared ground, at the foot of 

 the snow-drift." 



Anatomy. The Root, Fig. 38, A and 5, shows portions 

 of the transverse section of a root, about 4 mm thick. The 

 epidermis decays very quickly — as described by Hove- 

 LACQUE for the root of Pedicularis palustris — the epidermal 

 cells have already collapsed in roots not more than one mm 

 in thickness, and in the root figured they have disappeared 

 completely. The uppermost layer in Fig. 38, A, is the outer- 

 most layer of the primary cortex, which, on the whole, only 

 consists of 4 — 5 cell-layers. The cells have been very greatly 

 elongated tangentially during the secondary growth in thick- 

 ness, and are divided by a great number of thin radial walls; 

 the primary cortex persists for a long time, I found it even 

 on roots about one cm thick. The outer walls of the outer- 

 most layer are cuticularised. At the stage of development 

 figured in Fig. 38, an endodermis is not recognizable ; in quite 

 young roots faint Casparian dots can be demonstrated. The 

 structure of the secondary cortex is very characteristic, since 

 there is found in it a circle of radiating clefts, of which two 



