196 CLASS X. ORDER V. 



Stems spreading, round, dichotomous. Leaves ovate, oppo- 

 site. Flowers from the forks of the stem, crowded at the ends, 

 on peduncles shorter than themselves. Petals ohlons, white, a 

 little longer than the calyx, — In cultivated ground. — May. — 

 Annual. 



Cerastium viscosum. L. Viscid Ccrastium. 



Hairy, viscid, clifFiise ; leaves lanceolate-oblong. 

 In dry fields, &c. Introduced. — May, &;c. 

 Cerastium semidecandrum. L. Small Ctrastium. 



Hairy, viscid, flowers pentandrons, petals eniargi- 

 nate. 



A small species, sometimes of a reddish cast. — Sandy soils. — 

 Introduced. — May. 



Cerastium arvense. L. Field Chickweed. 



Leaves linear-lanceolate, obtuse, ciliate at base, 

 petals twice as long as the calyx. 



Flowers large, white. Naturalized in the same situations as 

 the others. — May, August. 



Cerastium tenuifolium ? Pursh. Narrow leaved Ceras- 

 tium. 



Pubescent, casspitose; leaves linear, mostly longer 

 than the internodes; petals obovate emarginate, three 

 times as long as the calyx. 



Stems round, hairy, ascending. Leaves narrow-lanceolate, 

 tapering upwards, subacute, pubescent, the lower ones longer 

 than the internodes. Segments of the calyx acute, hardly nerved. 

 Petals not very deeply cleft. — On the precipice, near Bellows' 

 falls, New Hampshire. — June. 



206. SPERGULA. 



Spergula arvensis. L. Corn Spurrey. 



Leaves whorled ; stalks of the fruit reflexed ; seeds 

 kidney shaped, imgnlar, rough. Sm. 



A weed in corn fields, by many of our farmers denominated 



