222 
IOWA ACADEMY OF SCIENCES. 
PORTULACACE^E. 
PORTULACA L. 
239. P. oleracea L. Purslane. A fleshy weed, very com- 
mon in cultivated ground, where it has become 
naturalized from its native home in the south- 
west, and tropical America. 
CARYOPHYLLACEJE. 
Agrostemma L. 
240. A . gitliago L. (. Lychnis githago Scop.) Corn 
Cockle. An European plant, adventive in wheat 
fields. 
Silene L. 
241. S. stellata (L.) Ait. Starry Campion. Common 
in woods. 
242. S. antirrhina L. Frequent in woods and waste 
places. 
243. S. noctiflora L. Introduced into waste places, 
Estherville. 
Vaccaria Medic. Cow-herb. 
244. V. vaccaria (L. ) Britton. ( Saponaria vaccaria L. ; 
Vaccaria vulgaris Host.) A common Euro- 
pean weed, adventive in wheatfields. 
Alsine L. 
245. A. longifolia (Muhl.) Britton. ( Stellaria longifo- 
lia Muhl.) Common in marshes. 
NYMPHiEACEiE. 
Nympeeea L. 
246. N. advena Sol and. (. Nuphar advena R. Br.) Yel- 
low Pond-lily. Common in lakes and ponds. 
Castalia Salisb. 
247. O. tuberosa (Paine) Greene. ( Nymphcea tuberosa 
Paine.) White Pond-lily. Once very com- 
mon in lakes and ponds, but becoming rare. 
RANUNCULACE^E. 
Caltha L. 
248. C. palustris L. Marsh Marigold. Rare: found only 
in a marshy spring in the woods north of Esther- 
ville. 
