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This species was classed with hiemale by Milde. but all its 

 affinities are those of ramosissimum, and it is probable that it 

 has been taken for that species. The secondary steins are rough 

 and without a microscopic comparison would easily pass for 

 small forms of that species. The stems appear to be strictly 

 annual. Not one of the several hundred specimens I have seen 

 has a stem a year old, and I have been unable to find a person 

 who has seen it in early spring. Rev. J. M. Bates, of Callaway, 

 Neb., says he has not seen it in spring over two or three inches 

 high. Specimens collected in July or August usually have dead 

 or dying tops. It fruits mostly in May, but may develop second- 

 ary stems later and continue its fruiting into mid-summer. Only 

 one label of all I have seen calls it annual. 



It was described by Alexander Braun from South Carolina. 

 Louisiana and Missouri, and is now accredited to New Jersey, 

 Virginia, and the West generally. I have seen only four speci- 

 mens from east of the Mississippi, one each from Illinois, Wis- 

 consin, Indiana and Ohio. It is possible that Braun's species is 

 composite and it is desirable to verify the eastern localities. It 

 is most common on the sandy bottom lands of the arid regions 

 of the West, where it is an important forage plant. It extends 

 from Texas and Southern California to British Columbia and 

 Assiniboia. It is peculiar to North America and has not yet 

 been seen from Mexico. I find it fairly constant in characters, 

 but it presents several forms of note. 



The roughness of the stems is quite variable, though never 

 great except in small stems or branches. The stems when young 

 are usually very rough, but the asperities are soon covered by 

 a coating of silex, and the markings may often be seen under 

 the surface even when smooth to the touch. 



VARIETIES. 



i. Scabrellum Eng. Ridges prominent, rough with small 

 cross-bands of silex, leaflets convex in the middle and with two 

 lateral rough ridges above, teeth subulate, black at base, mem- 

 branous at borders, mostly persistent. This is essentially Engel- 

 mann's description. I would add that the stems often look 

 rough, even without a lens, when tolerably smooth to the touch. 

 At times the whole epidermis is completely covered with short 

 bands and spots of silex. It is not uncommon to find a few very 



