4. CRUCIFERiE. 133 



by any second authority ; and they are eminently suspici- 

 ous until so corroborated. I am quite unprepared to assign 

 the range of altitude, and consequently the ranges of zone 

 and temperature also. The habitat of " East Harptree," 

 Somerset, is probably of slight elevation ; wliile some of 

 those in Yorkshire may be at 300 yards or upwards. I 

 suppose it to be 200' yards in Derbyshire. 



79. Draba verna, Linn. 



Area 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 * 17 18. 

 '^/C- ///.*/ South limit in Devon, Isle of Wight, Kent. <i-<-*.-<^^»^ 

 ^ North limit in Orkney and Ross-shire. 

 -^Estunate of provinces 18. Estimate of coimties 80. 



Latitude 50 — 60. British type of distribution. 



A. A. regions. Inferagrarian — Midarctic zones. 



Descends to the coast level, in the Peninsula. 



Ascends to 800 yards, or upwards, in E. Highlands. 



Range of mean annual temperatm-e 52 — 39. 



Native. Glareal and Rupestral. My compilation of lo- 

 calities shows this species to have been reported from near- 

 ly fifty counties. That it grows in all, or almost all the 

 rest, I can scarce doubt; though so small and eai-ly -flower- 

 ing a plant is overlooked by summer tourists. I have 

 traced the species to 400 yards up the Grampians. In as- 

 signing it to the arctic region, and to an altitude of 800 

 yards or upwards, I am taking in the variety found by Sir 

 William Hooker "on rocks near the lake upon Ben 

 Lawers." I estimate that lake to be at 800 yards (some 

 say, nearer 1000 yards) of elevation above the sea; being 

 2000 feet above Killin. For this species, as for many 

 others indicated from Devon, the true south limit is doubt- 

 less in Cornwall, though not recorded. 



