XXIV INTRODUCTION. 



Within it are the only Devonian stations of Physospermum cornvMense. 

 The species limited to it are : 



Nasturtium sylvestre. 

 Hyinricum linariifolium. 

 Altlicea officinalis. 

 Eiyilohium roseum. 

 Eryngium campestre. 

 Chcerophyllum Anthriscus. 

 Lactuca virosa. 

 Hieracium maculatum. 

 Carex axillaris. 

 C. vesicaria. 



TV. Plym District. — The boundaries are, north, the line of limit ; 

 west, the east of District in. ; south, the Sound and English Channel ; 

 east, a line drawn from between Shavercomb Head and Yealm Head, on 

 Dartmoor, across Shell Top and Hemerdon Ball, to pass thence about 

 one mile east of Plympton Maurice, and follow the road from Elburton, 

 through Staddiscombe, to the coast at Wembury Pomt. 



Withm this District the larger portion of the limestone beds are found, 

 and these have a considerable effect on its flora. 



The followmg species are restricted to it : 



Ranunculus Drouetii. 



Diplotaxis tenuifolia. 



Callitriche ohtusangula. 



Tillcea muscosa. 



(Enanthe pimpinelloides. 



Picris hieracioicles. 



Hieracium vulgatum. 



Mentha rubra. , 



Potamogeton j^cctinatus. 



Orchis Morio. 



Habenaria viridls. 



Ophrys apifera. 



Convallaria majalis. 



Allium oleraceum. 



Carex Pseudo-cyperus. 



Sclerochloa Borreri. 



A remarkable number of Euhi occur in the beautiful Plym Valley. 



V. Yealm District. — The boundaries are, north, a small portion of 

 District iv. and of vi., which meet above the fountain head of the Yealm ; 

 west, the east of District iv. ; south, the Channel ; east, a line passing 



