Hardy Exotic Plants for Naturalization. 63 



wet or moist rocks, rooting on them, somewhat as a 

 moss would, and forms sheets of starry flowers thereon. 



MoTintain Sand-wort. Arenaria montana. Europe. 

 Evergreen perennial j 4 to 6 inches ; white ; spring and 

 summer ; seed or division. — In good sandy loam, either 

 on bare level ground, or on banks or rocks. 



Biebersteln's Mouse-ear Chiokweed. Cerastium 

 Biebersteinii. Caucasus. Evergreen perennial; 2 to 6 

 inches ; white ; summer ; seed or division. — Banks, fringes 

 of shrubberies, rough, rocky places, or almost any kind 

 of situation, in ordinary soil. 



Large-flowered Cerastium. Cerastium grandi- 

 florum. Siberia. Evergreen perennial ; 2 to 6 inches ; 

 white ; summer ; seed or division. — Similar positions to 

 the foregoing; is not so common as the preceding or 

 following kind. 



Woolly Mouse-ear Chiokweed. Cerastium tomen- 

 tosum. Southern Europe. Evergreen perennial ; 2 to 6 

 inches; white; summer; seed or division. — Equally 

 useful and hardy as the two foregoing kinds. 



THE FLAX FAMILY. 



Alpine Flax. Linum alpinum. Austria. Herba- 

 ceous perennial ; 4 to 9 inches ; blue ; summer ; seed or 

 division. — Open rocky places, or fully exposed spots in 

 sandy soil, associated with the more vigorous alpines. 



Narbonne riax. Linum narbonnense. S. France. 

 Herbaceous perennial ; i to 2 feet ; blue ; summer ; seed 

 or division. — In deep sandy loam amidst medium-sized 

 herbaceous plants, or on banks, rocky or stony ground. 



