Euphorbia 



EUPHORBIACEAE 



643 



Jan. 



Feb. 



Mar. 



Apr, 



May. 



June 



July 



Aug. 



Sept. 



Oct. 



Nov. 



Dec. 



Miles 



50 



Map 1331 



Euphorbia glyptosperma Enqelr 



50 



Map 1332 



Euphorbia humistrata Enge! 



50 



Map 1333 

 Euphorbia maculata L. 



2. Euphorbia polygonifolia L. (Chamaesyce polygonifolia (L.) Small.) 

 Map 1329. This is a small prostrate species restricted to the beach of Lake 

 Michigan. 



Atlantic coast from N. S. to Fla. and on the shores of the Great Lakes. 



3. Euphorbia serpens HBK. (Chamaesyce serpens (HBK.) Small.) 

 Map 1330. On a rocky bar in Wilson Creek in Dearborn County and on the 

 bank of the Ohio River and in adjoining overflow land. Infrequent. 



Sw. Ont. to S. Dak., southw. to Mex. ; and S. A. 



4. Euphorbia glyptosperma Engelm. (Chamaesyce glyptosperma (En- 

 gelm.) Small.) Map 1331. I have found this spurge only three times 

 although it may be rather frequent since it can easily be mistaken for other 

 species of the genus. My specimens were found in dry sandy and gravelly 

 soil. 



Maine, Ont. to B. C, southw. to N. Y., Iowa, Tex., and Mex. 



5. Euphorbia humistrata Engelm. (Chamaesyce humistrata (En- 

 gelm.) Small.) Map 1332. All of our specimens except one are from the 

 southern half of the state. We have, however, three reports from the 

 northern half. It is to be noted that this species is separated with difficulty 

 from Euphorbia supina and this similarity may result in their confusion. 

 In the field Euphorbia humistrata is notably more glaucous than Euphorbia 

 supina. 



Ont. to Minn., southw. to N. J., Miss., and La. 



6. Euphorbia maculata L. (Contr. Gray Herb. 127: 74. 1939.) (Euphor- 

 bia nutans Lag., Euphorbia Preslii (Guss.) Arth., and Chamaesyce Lan- 

 singii Millsp.) Nodding Spurge. Map 1333. A common weed in all parts 

 of the state, usually in dry soil. It is found in fallow and cultivated 

 grounds, along roadsides and railroads, and in open woodland and pastures. 



My Randolph and Tipton County specimens were named Chamaesyce 

 Lansing ii Millsp. by C. F. Millspaugh and I reported them as such. I am 

 now referring them to this species. 



Mass., Ont., Wis., and Nebr., southw. to Fla. and Tex. 



