DIANDRIA DIGYNIA. 9 



plant should rise to the surface, and expand its blossoms 

 in the air. They are then found to contain only air, 

 which again gives place to water when the plant descends 

 to ripen its seeds at the bottom. 



11. LEMNA. 



1. L. trisulca, fronds stalked, proliferous, elliptic-lanceolate, 

 thin, serrate towards the point; roots solitary. Ivy-leaved Duck~ 

 weed. 



Hdb. Clear still waters, as in the pond at the Grieve's House. 

 June. 



2. L. minor, fronds obovate, flattish above and beneath ; roots 

 solitary. Lesser Duckweed. 



Hal. Ponds and ditches, common. June. 



12. SALVIA. 



1. S. verbenaca, leaves serrated, sinuated, rugose, the lower 

 ones stalked ; bracteas heart-shaped ; corrolla narrower than the 

 calyx, violet blue. Wild Clary. 



Hob. Grassy banks. Castle-banks, plentiful, Thomp. The 

 same species, and not S. pratensis, as stated by WALLIS, 

 grows sparingly near the ruin of the Abbey in Holy 

 Island, and at Norham Castle. June. 



It is remarkable that when the ripe seeds are immersed in 

 water, they speedily swell out to the size of peas or frog- 

 spawn. 



II. DIGYNIA. 



13. ANTHOXANTHUM. 



1. A. odoratum, panicle spiked, ovate-oblong, (yellow in age) ; 

 flowers longer than their awns, on short partial stalks. Sweet 

 Vernal Grass. 



Hab. Meadows and pastures, very common. May, June. If. 



In drying, this grass exhales the odour of Woodruff, and is 



one of the chief causes of the fragrance of new 



hay. 



A 3 



