1049 



Thalictrum Jlexuosiim, Reich. Ascends to an elevation of 300 

 yards (average annual temjDerature, 45 degrees), along the banks of 

 the Tees, below Holwick, Yorkshire. 



Barharea mdcjarift. Ascends to 200 yards (46 deg.), on the banks 

 of the Balder, near its junction with the Tees, Yorkshire. 



Erysimum Alliaria. Ascends to 200 yards (46 deg.), on hedge- 

 banks by the roadside near Cotherstone, Yorkshire. 



Arenaria serpyllifolia. Ascends to 400 yards (44 deg.), in a culti- 

 vated field near Langdon Bridge, Durham. 



Hypericum quadrangulum. Ascends to 350 yards (45 deg.), on 

 the roadside near the High-Force Inn, Durham. 



Hypericum hirsutum. Ascends to 350 yards (45 deg.), in the wood 

 behind the High-Force Inn, Durham. 



Geranium, lucidum. Ascends to 400 yards (44 deg.), along the 

 banks of Langdon Beck, near the bridge of the Alston road, Durham. 



Prunus spinosa. Ascends to 350 yards (45 deg.), amongst the 

 scars above Holwick, Yorkshire. 



Geum urhanum. Ascends to 350 yards (45 deg.), in the High- 

 Force Wood, Durham, with Poa Parnellii and Crepis succisaefolia. 



Agrimonia Eupatoria. Ascends to 250 yards, on the roadside 

 above Roraalakirk, Yorkshire. 



Potentilla fruiicosa. Descends below 150 yards (nearly 47 deg.), 

 at Greta Bridge, Yorkshire, Baines" Flora ; ascends to 400 yards (44 

 deg.), on the Durham side of the Tees, near its junction with Lang- 

 don Beck. 



Sanguisorha ojficinalis. Ascends to 450 yards (44 deg.), on the 

 lower portion of Falcon Glints, Durham. 



Epilohium parvijlorum. Ascends to 400 yards (44 deg.), in a 

 streamlet near Langdon Bridge, Durham. Much less hairy than the 

 ordinary lowland state. 



Circcea lutetiana. Ascends to 200 yards (46 deg.), on a wall near 

 the junction of the Balder with the Tees, above Cotherstone, York- 

 shire. 



each hundred yards in elevation. To avoid unnecessary repetition, the climatic zone 

 is only mentioned where the species has not been ascertained to occur in the same 

 zone before. As a general rule, the line of 4o° (900 feel) may be considered as the 

 boundary between the midagrarian and superagrarian zones in this latitude ; and that 

 of 42° (1800 feet) as the upward limit of cultivation. In a few cases, where I have 

 personally collected the species in the specified locality, the authority for its occur- 



