ERYNGIUM 



Leaves. — Radical, green with. white margin, three-foliate; leaflets 

 ovate, serrate. 

 Flowers. — Cream-white, in rather large bractless umbels. 

 Calyx-teeth. — Obsolete. 

 Fruit. — Ovate, glabrous, destitute of oil cells. 



This well-known foliage plant is easily established, but difficult 

 to uproot when established. The leaves stand on rather long 

 petioles, so that the pretty green and white border that it makes is 

 about six inches high. Each leaflet has a green centre and a cream- 

 white margin and holds these colors under all vicissitudes of fortune. 



The plant is so tolerant of conditions that in Europe it is con- 

 sidered a weed, but it has not become such in this country. 



SEA HOLLY. BLUE THISTLE. STAR THISTLE. ERYNGIUM 



Erjmgium amethysHum. 



An ancient name of uncertain meaning. 



A plant with the aspect of a thistle, but blue in stem, leaf, and flower. 

 Native to the southern Alps. Summer. 



Stems. — Rigid, steel-blue or purplish. 



Leaves. — Stiff and spiny. 



Flower-heads. — Both terminal and axillary, surrounded by an in- 

 volucre of long spiny bracts. 



Flowers. — Blue, in heads, not umbels; a pointed bract under each 

 flower. 



Calyx. — Five awl-shaped teeth. 



Petals. — Five, blue; styles two; fruit top-shaped. 



The Sea Hollies, or Eryngiums are a curious and interesting 

 group which have varied so far from their forbears that their 

 nearest relations can scarcely claim an acquaintance. Their entire 

 physical structure is a challenge; they out-thistle the thistles; 

 their swords are never sheathed; they sleep on their arms. 

 Nevertheless, they are not thistles at all, but belong to the un- 

 armed race of Umbellifera — blood brothers to the carrot and the 

 parsnip. 



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