iowa academy of sciences. 221 ■ 



chenopodiace.e. 



Chknopodium L. 



229. C. album L. Lamb's-quarters, Pigweed. A com- 



mon weed, naturalized from Europe. 



230. r. hoscianum Moq. (jroosefoot. Common in 



woods. 



231. C. /ii/hri(/tnn L. Maple-leaved Goosefoot. Woods, 



Iowa lake, and probably elsewhere in the 

 country. 

 Salsola L. 



232. S. trar/its L, {S. h-ali var. tragus Moq.) Russian 



Thistle. A noxious European weed, very com- 

 mon and troublesome in dry years. 



amaranthace.e. 



Amaranthus L. 



233. A. reti-qffexus L. Pig-weed. A very common weed,. 



naturalized from tropical America. 



234. A. b/lfoides S. Watson. A common weed around 



dwellings, naturalized from the western plains. 



235. A. grwcizans L. (A. albut; L.) Our commonest 



tumble-weed, introduced from tropical America. 



ACNIDA L. 



236. A. taniayhciua (Niitt.) Wood. Frequent along 



streams, and in low cultivated ground— occa- 

 sionally in marshes; on muskrat houses. 



NYCTAGINACE^. 



Allionia Loefl. 



237. A nydayinca Michx. (Ox//bajilnis nyctagineiiH 



Sweet.) Frequent on knolls and in cultivated 

 fields. 



238. A. liirsutaPursh. (Oxyba^'/ius hirsufusS'weet.)B.a.re; 



dry ground along road south of Iowa Lake. 



